Banana Fritter Coffee Cake

Ingredients

Instructions

1. Preheat the oven to 350°F (175°C). Grease a 9x9-inch light-colored metal pan. Line it with two long, crossed sheets of parchment, covering the entire bottom and all four sides with generous overhangs. This lets you peel the paper away without scraping off the caramelized edges.
2. Make the crumble: combine the all-purpose flour, brown sugar, granulated sugar, cinnamon, salt, cold butter, and vanilla bean paste. Work together with your fingertips, squeezing the mixture into large clusters. Refrigerate while you prepare the remaining components.
3. Make the cinnamon filling: stir together the brown sugar, melted butter, cinnamon, all-purpose flour, and salt until evenly combined. Set aside.
4. Thoroughly mash the banana and weigh the amount listed in the ingredients. In a large bowl, whisk it with the brown sugar, granulated sugar, oil, yogurt, milk, vanilla bean paste, and banana emulsion until evenly combined.
5. Sift the all-purpose flour, cornstarch, baking powder, baking soda, salt, and nutmeg directly over the wet ingredients. Gently whisk just until no dry streaks remain. Avoid overmixing.
6. Spread a little over half the batter evenly into the prepared pan. Spoon the cinnamon filling over the batter and gently spread it all the way to every parchment-lined edge to create the caramelized sides.
7. Spoon the remaining batter over the filling in small dollops. Gently connect and smooth them without disturbing the cinnamon layer underneath.
8. Scatter the chilled crumble evenly over the top, keeping it in large clusters.
9. Bake with a foil-lined sheet pan on the rack underneath to catch any drips. Start checking the topping around 40 minutes and tent loosely with foil once it is browned enough. I tented mine at 45 minutes and took it out at 55 minutes total. Many ovens are slower than mine, so allow more time as needed.
10. Check the center before removing the cake: it should be fully set, and a tester inserted into a cake portion, avoiding the cinnamon filling, should come out clean or with moist crumbs rather than wet batter. An internal temperature around 210°F can support these checks, but also check the center's firmness and the tester. Keep baking under the foil if the center is still wet.
11. Rest the cake in the pan for at least 30 minutes. Using the parchment overhangs, carefully lift it onto a wire rack. Gently peel the paper away from the sides. Let it cool longer if needed; it should be warm and sturdy enough to handle before turning it.
12. Place a second wire rack upside down over the cake. Hold both racks firmly, supporting the cake between them, and flip the whole assembly so the cake is upside down. Remove the upper rack and gently peel all parchment from the base. Put that rack against the exposed base, hold both racks securely, and flip again so the cake is right side up. Remove the top rack.
13. Set the rack and upright cake over a parchment-lined tray. Whisk the powdered sugar, vanilla bean paste, and milk until completely smooth.
14. Pour about half the glaze over the top. Support the cake securely underneath and gently tip it over the tray to drain the excess, leaving a thin coating. Coat all four sides with more glaze as needed, letting it drip through the rack. Return the cake upright to the rack. You will have extra glaze - the entire batch is not meant to stay on the cake.
15. Refrigerate for 20-30 minutes, or freeze for 10-15 minutes, then check the glaze. Allow additional time as needed until completely set before slicing.