Obsessed Cakes
Brownie Lava Cake
A full-size brownie lava cake with soft chocolate layers, glossy brownie batter filling, chewy brownie pieces, and silky chocolate buttercream.
- Prep
- 1 hr 20 min
- Bake
- 22-25 min
- Total
- 4 hr
- Yield
- One three-layer 8-inch cake
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Ingredients
Chocolate Cake
- 330 g (about 2 3/4 cups) cake flour, sifted
- 70 g (about 2/3 cup + 1 tablespoon) Dutch-process cocoa powder
- 15 g (about 2 tablespoons + 1/2 teaspoon) cornstarch
- 2 1/2 teaspoons baking powder
- 1/2 teaspoon baking soda
- 1 teaspoon fine sea salt
- 360 g (about 1 3/4 cups + 1 tablespoon) granulated sugar
- 395 g (about 1 1/2 cups + 2 tablespoons) milk, room temperature
- 2 teaspoons apple cider vinegar
- 120 g (about 7 tablespoons + 2 1/2 teaspoons) plain unsweetened yogurt
- 210 g (about 3/4 cup + 3 tablespoons) neutral oil, such as grapeseed, canola, or sunflower
- 2 teaspoons vanilla bean paste
Brownie Lava
- 100 g (about 7 tablespoons + 1 1/2 teaspoons) light brown sugar, packed
- 50 g (about 1/4 cup) granulated sugar
- 70 g (about 5 tablespoons) butter
- 40 g (about 6 tablespoons + 2 teaspoons) Dutch-process cocoa powder
- 40 g (about 1/3 cup) all-purpose flour
- 80 g (about 1/3 cup) heavy cream
- 1 teaspoon vanilla bean paste
- 1/4 teaspoon fine sea salt
- 70 g (about 6 tablespoons + 2 teaspoons) chopped chocolate chips, about 50% cocoa
- 60-90 g (about 1/4 cup to 6 tablespoons) milk, to thin to desired consistency
Brownie Squares
- 100 g (about 7 tablespoons + 1 1/2 teaspoons) light brown sugar, packed
- 50 g (about 1/4 cup) granulated sugar
- 90 g (about 1/3 cup + 1 tablespoon) butter, room temperature
- 60 g (about 1/2 cup + 2 tablespoons) Dutch-process cocoa powder
- 120 g (about 1 cup) all-purpose flour
- 2-3 tablespoons heavy cream
- 1 teaspoon vanilla bean paste
- 1/2 teaspoon fine sea salt
- 70 g (about 6 tablespoons + 2 teaspoons) chopped chocolate, about 50% cocoa
Chocolate Buttercream
- 339 g (about 1 1/2 cups) butter, room temperature
- 510 g (about 4 1/4 cups) powdered sugar, sifted
- 68 g (about 2/3 cup + 2 teaspoons) Dutch-process cocoa powder
- 1/4 teaspoon fine sea salt
- 2 teaspoons vanilla bean paste
- 50-80 g (about 3 tablespoons + 1 teaspoon to 1/3 cup) heavy cream, starting with 3 tablespoons and adding to desired texture
Instructions
- Make the cake layers. Preheat oven to 350°F (175°C). Grease and line three 8-inch pans with parchment.
- In a medium bowl, whisk together the cake flour, cocoa powder, cornstarch, baking powder, baking soda, and salt. Sift well so no cocoa clumps remain.
- In a large bowl, whisk together the sugar, room-temperature milk, apple cider vinegar, yogurt, oil, and vanilla bean paste.
- Sift the dry mixture into the wet mixture and fold gently until smooth.
- Divide the batter evenly between the prepared pans and bake for 22-25 minutes, until the tops spring back. Cool for 10-15 minutes in the pans, then remove and place on a wire rack to cool completely.
- Make the brownie lava. Melt the butter with both sugars over medium heat until glossy.
- Whisk in the cocoa powder and flour until the mixture looks paste-like.
- Gradually stream in the cream until the mixture is molten and thick. Stir in the vanilla bean paste and salt.
- Let the lava cool until just above room temperature. Fold in the chopped chocolate so it softens without fully melting.
- Let the lava cool to room temperature or slightly below. Whisk in 60-90 g milk at the very end, until your desired consistency is reached, and use immediately.
- Make the brownie squares. Cream the room-temperature butter with both sugars until fluffy.
- Mix in the cocoa powder, flour, and salt until sandy. Add the vanilla bean paste and cream, then mix to a stiff dough.
- Fold in the chopped chocolate. Press into a parchment-lined 9 x 9-inch pan, chill for 30 minutes, then cut into small squares.
- Make the chocolate buttercream. Beat the butter until creamy. Add the powdered sugar, cocoa powder, salt, and vanilla bean paste. Beat on low, then whip on high until fluffy.
- Slowly stream in the cream and mix on low until the buttercream is light, smooth, and silky.
- Assemble the cake. Place the first cake layer on a board. Spread on a thin layer of buttercream, then pipe a buttercream dam around the edge.
- Spoon brownie lava inside the dam and scatter in a few brownie squares.
- Repeat with the second cake layer, then add the final cake layer.
- Frost the outside with chocolate buttercream.
- Garnish with more brownie squares and drizzle extra lava over the top.