Lava Cakes
White Chocolate Blondie Lava Cake
This White Chocolate Blondie Lava Cake turns every irresistible stage of a blondie into one layer cake. Soft vanilla cake surrounds a brown sugar blondie batter lava, chilled white chocolate cookie-dough pieces, and silky vanilla bean buttercream.
The buttercream dams are intentionally strong, the filling stays fluid, and the cookie-dough pieces bring the soft, scoopable blondie texture that usually disappears once the pan reaches the oven.
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Thinking out loud
Every Stage Is the Best Stage
White chocolate chip blondies are the best at every stage. They are the best right after the flour disappears into the dough, when the batter is still soft and scoopable. They are the best when they come out of the oven too early, and when they are fully baked but still too unstable to cut. They are even the best after cooling completely or chilling overnight.
Somehow, every stage feels like the most important one. I wanted a cake that celebrated all of them - soft vanilla layers, blondie batter lava, white chocolate cookie-dough pieces, and plenty of vanilla bean buttercream to hold everything together.
Ingredient notes
Key ingredients
Light brown sugar
Brown sugar gives both the lava and cookie-dough pieces their warm blondie flavor and soft texture.
White chocolate chips
Finely chopped white chocolate spreads little creamy bites throughout the cookie-dough pieces without making them difficult to cut.
Vanilla bean paste
Vanilla bean paste carries through the cake, lava, cookie dough, and buttercream so every component tastes connected.
Cake flour and cornstarch
This combination keeps the vanilla layers soft and fine-crumbed while still giving the tall cake enough structure.
Brands I used for this recipe
These are preferences, not requirements. If you choose the non-dairy route, these are the products I test with. Dairy equivalents can be used at the same listed amounts and temperatures.
Forager Unsweetened Plain Yogurt
Plain unsweetened yogurt adds moisture, acidity, and body so the crumb bakes up tender without tasting tangy.
Silk Original Unsweet
Milk affects how smoothly a batter, filling, or frosting comes together. Soy milk and Ripple tend to emulsify well because their protein and fat help create a creamy, cohesive finish.
Country Crock Plant Butter Sticks
Use butter sticks for buttercream and fillings that need to hold their shape.
Country Crock Heavy Plant Cream
Cream affects the lava's flow and how the buttercream sets after resting.
King Arthur Unbleached Cake Flour
I use King Arthur Unbleached Cake Flour for this recipe.
Rising Star Baking Supply Vanilla Bean Paste
I use Rising Star Baking Supply Vanilla Bean Paste for this recipe.
Testing notes
Why this works
Keep the lava soft
Stir the butter, sugars, and cream gently as they melt, then cool the filling completely so it settles into a soft blondie-batter consistency.
Why the dam needs to be strong
This looks like a lot of buttercream because it is. You need enough to frost the cake and pipe tall, complete dams that can hold the blondie batter lava securely between the layers.
Keep the cookie dough chilled
Chilling firms the white chocolate cookie dough so it can be cut or broken into clean pieces for layering and garnish without blending into the lava.
Step by step
How It All Comes Together
Step 1
Spread a thin buttercream base
Start with completely cool cake layers, room-temperature lava that is fluid but not warm, and chilled cookie-dough pieces. Place the first cake layer on a cake board. Spread a thin, even layer of buttercream across the top with an offset spatula. Keep enough buttercream for both filling borders and the outside of the cake.
Spread the buttercream into a thin, even base before piping the border. Step 2
Pipe a tall, continuous dam
Pipe a raised ring of buttercream around the full edge of the layer, joining the ends without a gap. This border holds the soft filling inside and supports the next cake layer. Keep the center lower than the border so there is room for the lava and dough.
Join the ends of the ring so there is no opening for the lava to escape. Step 3
Pour and spread the blondie lava
Pour a controlled amount of completely cooled lava into the center. Use the back of a spoon to ease it outward into an even layer inside the ring. Stop below the top of the dam, leaving room for the cookie-dough pieces. Keep the spoon inside the border so you do not knock it down.
Pour into the center first, keeping the buttercream ring clear. 
Use the back of a spoon to spread the lava without flattening the dam. Step 4
Add the chilled cookie-dough pieces
Scatter the chilled pieces evenly over the lava. Keep them inside the buttercream ring and avoid piling them above the dam. The next cake layer should sit on the buttercream border rather than a mound of filling. Save some dough and lava for the top.
Distribute the pieces across the filling instead of making a mound in the middle. 
Leave the outer buttercream border clear to support the next cake layer. Step 5
Repeat the filling and finish the stack
Lower the second cake layer onto the first filled layer, lining up the edges without pressing hard on the filling. Repeat the thin buttercream base, tall dam, cooled lava, and chilled dough pieces. Add the third cake layer with both hands supporting it. Check the stack from the side and adjust gently until the layers line up.
Repeat this raised border on the second layer, keeping the center lower than the rim. 
Support the cake layer with both hands as you line it up with the layers below. Step 6
Seal the sides and crumb coat
Pipe buttercream into the gaps between the stacked layers, then smooth it into a thin coating around the sides. Spread a thin coat over the top as well to catch loose crumbs. It is fine to see the cake through this first coat. Refrigerate until the buttercream feels firm before adding the final coat.
Fill the gaps between the cake layers before smoothing the sides. 
The cake can still show through a thin crumb coat. Cover the top too before chilling. 
Spread buttercream across the top to complete the coating. Step 7
Frost and decorate
Use the remaining buttercream to finish the top and sides of the chilled cake. Arrange the reserved cookie-dough pieces on top, then drizzle with cooled blondie lava. The cake layers and cookie-dough pieces contain sprinkles; leave the optional buttercream sprinkles out for the smooth finish shown here.
Add the cookie-dough topping, then drizzle the cooled lava over it. The finished cake has a light buttercream coating, cookie-dough pieces, and a blondie drizzle. Step 8
Slice to show the layers
Cut while the buttercream is firm for a more controlled slice. Let each slice sit briefly before serving if you prefer a softer center. Keep any extra lava at room temperature for serving alongside the cake.
Slice while the buttercream is firm, then let the slice soften briefly before serving.
From Instagram
Watch the reel
Watch the vanilla layers, blondie batter lava, white chocolate cookie-dough pieces, and vanilla bean buttercream come together.
Open the reelTroubleshooting
If This Happens
The blondie lava is too loose to stack
Let it cool completely before judging it. The filling should be soft and fluid but no longer warm when it goes inside the buttercream dam.
The cookie dough is smearing into the filling
Chill it until firm enough to break into distinct pieces, then keep those pieces cold until assembly.
The filling is pushing through the buttercream
Pipe a tall, unbroken dam and use a little less lava and cookie dough. Keep the filling below the top edge so the next layer rests on buttercream.
The cake feels unsteady after stacking
Apply the crumb coat and refrigerate the cake until the buttercream feels firm before adding the final coat and decorations.
Before you slice
Texture and serving notes
Slice the cake while chilled for the cleanest layers, then let individual slices soften briefly before serving.
Keep extra blondie batter lava at room temperature and spoon it over slices when you want a looser flow.
Keep it good
Storage
Fridge
Keep the assembled cake covered in the refrigerator.
Fridge
Store extra blondie batter lava and cookie-dough pieces separately in covered containers in the refrigerator.
Recipe FAQ
Questions that come up
Can I use vanilla extract instead of vanilla bean paste?
Yes. Vanilla extract can replace the vanilla bean paste in the same listed amount, although I prefer the fuller flavor and visible flecks from vanilla bean paste.
Can I make the components ahead?
Yes. Bake and chill the cake layers, make the cookie dough, and prepare the blondie lava ahead of assembly. Keep the cookie dough chilled, and bring the lava to room temperature so it is fluid but not warm when it touches the buttercream.
Should I weigh the ingredients or use volume measurements?
I strongly recommend weighing the ingredients in grams for the most reliable result. Volume measurements are included for convenience, but the amount in a cup can change depending on how an ingredient is filled, packed, or poured. These recipes are easy to follow, but their ratios are precise, so I cannot guarantee the exact same result when volume measurements are used. I still use teaspoons and tablespoons for small amounts like leaveners, salt, spices, and flavorings because those are the most practical measurements.
Can I make this recipe gluten-free?
I have not tested this recipe with gluten-free flour, so I cannot guarantee the same texture, rise, or structure. If you would like to experiment, a cup-for-cup (1:1) gluten-free baking blend intended to replace all-purpose flour is the best place to start. Results may differ from the recipe as written.
Can I use all-purpose flour instead of cake flour?
Yes, of course. Replace the cake flour with the same amount of all-purpose flour by weight. The cake will have a slightly sturdier, less delicate crumb, but it will still be great.
More lava cakes to try
- Prep
- 1 hr
- Bake
- 22-26 min
- Total
- About 4 hr, including cooling, chilling, and assembly
- Yield
- One three-layer 8-inch cake
Measurement note
For the closest match to the recipe I tested, use grams. Volume measurements are included for convenience, but cups can vary, so I cannot guarantee the exact same result when measuring by volume.
Ingredients
Tap each ingredient as you use it.
Volume measurements use US cups and level spoons and are approximate. Spoon flour and powdered sugar into the cup, level, then sift if directed. For cocoa and freeze-dried fruit powders, scoop the unsifted powder and level without packing, then sift if directed. Measure sprinkles loosely and level. Pack brown sugar. For ingredients marked "weigh for accuracy", use the listed grams.
Vanilla Cake Layers
- 300 g cake flour
- 25 g cornstarch
- 2 1/4 teaspoons baking powder
- 1/2 teaspoon baking soda
- 3/4 teaspoon fine sea salt
- 300 g granulated sugar
- 120 g neutral oil
- 200 g plain unsweetened yogurt
- 240 g milk
- 1 tablespoon apple cider vinegar
- 2 tablespoons vanilla bean paste
- 90 g rainbow sprinkles, plus more for the pan tops (optional)
Blondie Batter Lava
- 100 g butter
- 200 g granulated sugar
- 60 g light brown sugar, packed
- 80 g cream, plus more if needed
- 1/2 teaspoon fine sea salt
- 1 teaspoon vanilla bean paste
Blondie Cookie Dough Pieces
- 90 g butter, room temperature
- 100 g light brown sugar, packed
- 50 g granulated sugar
- 180 g all-purpose flour, prepared for no-bake use
- 2-4 tablespoons cream, as needed
- 1 teaspoon vanilla bean paste
- 1/2 teaspoon fine sea salt
- 70 g white chocolate chips, finely chopped
- 60 g rainbow sprinkles
Vanilla Bean Buttercream
- 454 g butter, room temperature (4 sticks)
- 1 teaspoon fine sea salt
- 1 tablespoon vanilla bean paste
- 560 g powdered sugar, sifted
- 90-120 g cream, room temperature
- 60 g rainbow sprinkles, optional
Pan used
I use Fat Daddio's 8-inch anodized aluminum round cake pans for this recipe.
Instructions
- 1Make the vanilla cake layers. Preheat the oven to 350°F. Grease three 8-inch round cake pans and line the bottoms with parchment paper.
- 2In a large bowl, whisk the granulated sugar, oil, plain unsweetened yogurt, milk, apple cider vinegar, and vanilla bean paste until fully smooth and emulsified.
- 3Sift the cake flour, cornstarch, baking powder, baking soda, and salt directly over the wet ingredients. Whisk gently just until combined and smooth. Do not overmix.
- 4Gently fold the rainbow sprinkles into the finished batter, stopping as soon as they are distributed. Divide the batter evenly among the prepared pans and tap them lightly to release large air bubbles. Add a few extra sprinkles to the pan tops if you like.
- 5Bake for 22-26 minutes, until the tops are set and a tester comes out clean or with a few moist crumbs.
- 6Cool the cakes in their pans for 10-15 minutes, then turn them out onto wire racks and cool completely before assembly.
- 7Make the blondie batter lava. Melt the butter, granulated sugar, light brown sugar, and cream together over medium heat, stirring gently until the mixture comes together.
- 8Remove the lava from the heat and stir in the salt and vanilla bean paste until glossy. Add a little more cream if you want a looser flow, then cool completely to room temperature.
- 9Make the blondie cookie-dough pieces. Beat the room-temperature butter, light brown sugar, and granulated sugar until light and fluffy.
- 10Mix in the prepared all-purpose flour, salt, and vanilla bean paste. Add the cream gradually until the dough is soft but scoopable.
- 11Fold in the finely chopped white chocolate chips and rainbow sprinkles. Chill the dough briefly, then break it into pieces or cut it into small squares. Keep the pieces chilled until layering and garnish.
- 12Make the vanilla bean buttercream. Beat the room-temperature butter on medium-high speed for 3-4 minutes, until pale and fluffy. Mix in the salt and vanilla bean paste.
- 13Add the sifted powdered sugar in 3-4 additions, mixing until incorporated before adding the next portion.
- 14With the mixer on low, slowly stream in 90 grams of the room-temperature cream. Add more cream only as needed to reach a smooth, pipeable consistency. The buttercream will firm slightly as it rests. For a sprinkle buttercream, fold in the optional rainbow sprinkles at the end; leave them out for the smooth finish shown in the photos.
- 15Prepare to assemble. Make sure the cake layers and blondie lava are completely cool, the lava is fluid but not warm, and the cookie-dough pieces are chilled.
- 16Place the first cake layer on a cake board. Spread a thin layer of buttercream over the cake, then pipe a tall, unbroken buttercream dam around the edge.
- 17Spoon a controlled layer of blondie batter lava inside the dam, keeping it below the top edge. Scatter chilled cookie-dough pieces over the lava without overfilling the layer.
- 18Add the second cake layer and repeat with the thin buttercream layer, dam, lava, and chilled cookie-dough pieces. Top with the final cake layer.
- 19Apply a thin crumb coat and chill the stacked cake until firm. Finish with the remaining vanilla bean buttercream.
- 20Decorate with additional blondie batter lava and chilled cookie-dough pieces, keeping the lava cool enough that it does not melt the buttercream.
Meet the baker
Angela Heckler
Angela Heckler is the recipe developer, baker, and photographer behind Obsessed Cakes. Her Old-Fashioned Donut Loaf series is a growing collection of cake-donut-inspired loaves with soft, deeply moist crumbs, buttery streusel, and crackly glaze. Angela develops and tests every recipe in her Arizona kitchen. Follow Obsessed Cakes on Instagram, TikTok, and YouTube.
Made it? Tell us.
Ratings and reviews
I’ve made this cake twice, and it’s been absolutely fabulous! The second time I made it, I swapped out this frosting for the salted honey frosting and it was over the top delicious! I believe the salted honey frosting came from a cornbread cake recipe… I can’t remember exactly which one. I think the Blondie dough for this recipe is one of my favorites of all the lava cake recipes… I’ve made a bunch of them 😂
Yummmmm!! Love the creativity! I haven't made this one in a bit, now you make me want to make it again! haha :) Thank you so much for sharing!
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