Frozen bananas in a cake? Heck yes. Reducing the juice from these frozen fruits adds a nutty, caramelized flavor that takes this Banana Cake with Brown Sugar Hazelnut Buttercream to the next level. Top with a buttercream inspired by penuche, a brown sugar-based fudge reminiscent of Southern pralines, and this cake is downright irresistible.
Banana Cake with Brown Sugar Hazelnut Buttercream
Makes 1 (8-inch) cake
Ingredients
- 3 large frozen overripe bananas (525 grams), unpeeled
- ¼ cup (57 grams) unsalted butter, softened
- 1⅓ cups (267 grams) granulated sugar
- 2 large eggs (100 grams)
- 2 cups (250 grams) all-purpose flour
- 1 teaspoon (5 grams) baking soda
- ½ teaspoon (1.5 grams) kosher salt
- 1 cup (240 grams) sour cream
- 2 teaspoons (8 grams) vanilla extract
- Chocolate-Hazelnut Filling (recipe follows)
- Brown Sugar Hazelnut Buttercream (recipe follows)
- Praline Hazelnuts (recipe follows)
Instructions
- Thaw frozen unpeeled bananas in a medium bowl, reserving any juices during thawing process. Peel bananas, and place fruit in a fine-mesh sieve over bowl. Mash bananas, and press gently to collect juices but do not push fruit through sieve. Reserve 1½ cups (341 grams) mashed banana. Squeeze banana peel firmly over sieve to collect any remaining juice. In a stainless steel saucepan, heat banana juice over medium heat. Cook until reduced to 3 tablespoons (45 grams); set aside.
- Preheat oven to 350°F (180°C). Butter and flour 2 (8-inch) square tall-sided cake pans. Line bottom of pans with parchment paper.
- In the bowl of a stand mixer fitted with the paddle attachment, beat butter and sugar at medium speed until fluffy, 3 to 4 minutes, stopping to scrape sides of bowl. Add eggs, one at a time, beating well after each addition.
- In a medium bowl, whisk together flour, baking soda, and salt. With mixer on low speed, gradually add flour mixture to butter mixture alternately with sour cream, beginning and ending with flour mixture, beating just until combined after each addition. Fold in reserved 1½ cups (341 grams) mashed banana, reserved 3 tablespoons (45 grams) banana juice reduction, and vanilla. Divide batter between prepared pans, smoothing tops with an offset spatula.
- Bake until a wooden pick inserted in center comes out clean, about 25 minutes. Let cool in pans for 10 minutes. Remove from pans, and let cool completely on wire racks.
- Spread Chocolate-Hazelnut Filling between layers, and spread Brown Sugar Hazelnut Buttercream on top of cake. Top with Praline Hazelnuts.
Chocolate-Hazelnut Filling
Makes 1½ to 2 cups
Ingredients
- ½ cup (113 grams) unsalted butter, softened
- 3 cups (360 grams) confectioners’ sugar
- 2½ tablespoons (37.5 grams) heavy whipping cream
- ½ cup (43 grams) unsweetened cocoa powder
- ¼ cup (64 grams) chocolate-hazelnut spread*
Instructions
- In the bowl of a stand mixer fitted with the paddle attachment, beat butter at medium speed until creamy. Gradually add confectioners’ sugar and cream, beating until smooth. Add cocoa and chocolate-hazelnut spread, beating to combine. (Do not overmix.)
Brown Sugar Hazelnut Buttercream
Makes 2 cups
Ingredients
- 1 cup (220 grams) firmly packed dark brown sugar
- ½ cup (113 grams) unsalted butter
- ¼ cup (60 grams) warm whole milk (105°F/40°C to 110°F/43°C)
- 3 cups (360 grams) confectioners’ sugar
- 3 tablespoons (48 grams) chocolate-hazelnut spread*
- 1 teaspoon (3 grams) kosher salt
Instructions
- In a small saucepan, bring brown sugar and butter to a boil over medium-high heat. Boil for 1 minute. Remove from heat, and let cool for 15 minutes. Stir in warm milk.
- In the bowl of a stand mixer fitted with the whisk attachment, beat brown sugar mixture, confectioners’ sugar, chocolate-hazelnut spread, and salt at medium speed until lightened in color, about 2 minutes. Use immediately.
Notes
*We used Nutella.
Praline Hazelnuts
Makes 3 cups
Ingredients
- 2 cups (226 grams) chopped raw hazelnuts
- ¼ cup (50 grams) granulated sugar
- 1 teaspoon egg white (3 grams)
Instructions
- Preheat oven to 200°F (93°C). Line a sheet pan with parchment paper.
- In a medium bowl, whisk together hazelnuts, sugar, and egg white. Pour hazelnuts onto prepared pan.
- Bake for 12 minutes.
