Preheat the oven to 325F/163C convection (325F/163C conventional) and grease and line an 8x8” pan with baking spray and parchment paper (leaving an overhang to easily remove them).
Weigh the bananas after peeling them and then mash them until they look like banana puree.
2 (250g) medium bananas
Place the butter and chocolate in a medium, heat proof bowl and microwave for 1 minute, remove and stir until the chocolate and butter is melted and combined.
1/2 cup (113g) salted butter, 1 cup (6oz) chocolate chips
In a large bowl, place the granulated sugar, cocoa powder, vanilla and eggs. Whisk them together aggressively for 2-3 minutes, until the mixture is completely smooth.
1 1/4 cup (250g) granulated sugar, 2 large eggs, 1 tsp vanilla extract, 1/3 cup (26g) Dutch-process cocoa powder
Add in the melted chocolate and butter and whisk until the mixture is fully combined.
Add in the mashed bananas and whisk together until they're completely combined.
Add in the flour and salt and whisk just until there’s only a few streaks of flour left.
1 cup (120g) all-purpose flour, 1/2 tsp fine sea salt
Fold in the rest of the chocolate chips and spread into the prepared pan.
1/2 cup chocolate chips
Bake for 40-45 minutes. The top should be thin and crackly and puffed in the enter.
Tap it against the counter a couple of times, it should deflate a little but not be jiggly at all. When you press on it, it should feel soft underneath but not liquid-y.
Allow to cool in the pan for 30-60 minutes. Refrigerate for a little if you want clean slices. Top with a pinch of sea salt flakes or top with whipped cream and banana slices.
1 banana slices, whipped cream