Ingredients:
- 1/2 cup (115g) unsalted butter, melted and cooled
- 1 cup (200g) granulated sugar
- 1/3 cup (35g) unsweetened cocoa powder
- 2 large eggs
- 1 tsp (5ml) vanilla extract
- 1/2 cup (65g) all-purpose flour
- 1/4 tsp (1.5g) salt
- 2 ripe bananas, mashed (approx. 1 cup/240g)
- 1/4 cup (55g) unsalted butter, softened
- 1/2 cup (100g) brown sugar, packed
- 1 large egg
- 1 cup (125g) all-purpose flour
- 1 tsp (5g) baking soda
- 1/2 tsp (2.5g) cinnamon
- 1/4 tsp (1.5g) salt
Instructions:
- Preheat your oven to 350°F (175°C) and line an 8x8 inch square baking pan with parchment paper. Note: Leave an overhang for easy removal.
- In a mixing bowl, whisk the melted butter and granulated sugar until combined. Stir in the eggs and vanilla extract.
- Fold in the cocoa powder, flour, and salt until just combined. Whisk until no dry streaks remain but do not overbeat. Pour the chocolate batter into the prepared pan and smooth the top.
- In a second bowl, cream the softened butter and brown sugar until fluffy. Mix in the mashed bananas and egg.
- Gently fold in the flour, baking soda, cinnamon, and salt until no streaks of flour remain. Note: Over mixing here makes the banana layer rubbery.
- Spoon large dollops of the banana batter over the chocolate base. Distribute them evenly across the surface.
- Using a knife or offset spatula, gently drag the banana batter through the chocolate in a figure eight motion to create a swirl.
- Bake for 30-35 minutes until the edges are set and pulling away from the sides, and the center has a slight jiggle.
- Prepare the frosting by beating together the unsalted butter, powdered sugar, heavy cream, and vanilla extract until smooth and velvety.