This banana coffee cake tastes like a banana bread and coffee cake hybrid! It's soft, moist, and SO flavorful with a pecan and chocolate chip infused streusel topping.
Preheat oven to 350F and lightly grease a 9x9 baking pan with baking spray (or grease and flour, or line with parchment paper). Set aside and prepare streusel.
Streusel
Whisk together flour, sugars, cinnamon, salt, and nuts.
1 ¼ cup all-purpose flour, ½ cup light brown sugar, ⅓ cup granulated sugar, 1 ½ teaspoons ground cinnamon, ¼ teaspoon salt, ⅓ cup chopped pecans or walnuts
Drizzle melted butter over mixture and use a fork to claw together until you have a clumpy streusel. Measure out chocolate chips and set aside along with streusel for later.
6 Tablespoons unsalted butter, ⅓ cup mini chocolate chips
Cake
Combine butter and sugars in a large mixing bowl and use an electric mixer or stand mixer to beat until well creamed.
½ cup unsalted butter, ½ cup granulated sugar, ¼ cup light brown sugar
Add eggs and beat until well-combined. Stir in mashed banana and vanilla extract.
2 large eggs, 1 cup mashed overripe banana, 1 teaspoon vanilla extract
In a separate mixing bowl, whisk together flour, baking powder, baking soda, salt, and cinnamon.
1 ¾ cups all-purpose flour, 1 teaspoon baking powder, ¾ teaspoon baking soda, ¼ teaspoon ground cinnamon, ½ teaspoon salt
Add half of the dry ingredients to the wet and use a spatula to gently fold together until nearly combined. Add buttermilk, stir until nearly combined, then add remaining flour mixture and stir until just combined.
¼ cup buttermilk
Assembly
Spread the batter evenly into prepared pan. Top batter with the streusel mixture in an even layer and sprinkle mini chocolate chips overtop, if using.
Transfer to center rack of oven and bake for 45-50 minutes or until a toothpick inserted in the center comes out clean. Allow to cool before slicing and serving.
Notes
Storing
Store in an airtight container at room temperature for up to 3 days. This recipe may be tightly wrapped and frozen (after cooling completely) for several months.