- Nonstick vegetable oil spray
- 3 cups all-purpose flour
- 2 teaspoons baking soda
- 2 teaspoons kosher salt
- 1 1/2 cups sugar
- 1 cup (2 sticks) unsalted butter, room temperature
- 1/2 cup (packed) light brown sugar
- 3 large eggs
- 1 1/2 teaspoons vanilla extract
- 2 cups mashed very ripe bananas
- 1 cup sour cream
- 1 10-ounce bag mini chocolate chips
- 2 cups creamy peanut butter
- 1 1/2 cups powdered sugar
- 1 cup (2 sticks) unsalted butter, room temperature
- 2 1/2 teaspoons vanilla extract
- Chocolate chips, mini chocolate chips, and chocolate kisses
- Two 8x8x2″ cake pans
- Preheat oven to 350°F. Coat cake pans with nonstick spray. Line bottom of pans with parchment; coat paper. Whisk flour, baking soda, and salt in a medium bowl. Using an electric mixer, beat sugar, butter, and brown sugar in a large bowl until light and fluffy, about 3 minutes. Add eggs one at a time, beating to blend between additions and occasionally scraping down sides and bottom of bowl. Beat in vanilla.
- Add dry ingredients; beat on low speed just to blend. Add bananas and sour cream; beat just to blend. Fold in mini chips. Divide batter evenly among pans; smooth tops.
- Bake cakes until a tester inserted into the center comes out clean, about 35 minutes. Transfer to wire racks; let cool in pans for 10 minutes. Invert cakes onto racks; peel off parchment and let cool completely.
- Using an electric mixer, beat first 4 ingredients in a medium bowl until a light and fluffy frosting forms, 2-3 minutes.
- Place 1 cake on a platter. Spread 1 1/4 cups frosting over. Place remaining cake on top. Cover top and sides of cake with remaining frosting. Garnish with chocolate chips and kisses. DO AHEAD: Cake can be made 2 days ahead. Cover and chill. Let stand at room temperature for 1 hour before serving.