Preheat the oven to 325F/163C convection and grease and line an 8x8” pan with baking spray and parchment paper (leaving an overhang to easily remove them).
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.
3/4 cup (170g) salted butter, 1 cup (6oz) semi-sweet chocolate chips
In a large bowl, place the granulated sugar, brown sugar, cocoa powder, vanilla and eggs. Whisk them together aggressively for 2-3 minutes, until the mixture is completely smooth.
1 cup (200g) granulated sugar, 1/2 cup (95g) light brown sugar, 3 large eggs, 1 tsp vanilla extract, 1/2 cup (40g) Dutch-process cocoa powder
Add in the melted chocolate and butter and whisk until the mixture is fully combined.
Add in the flour and salt and whisk just until there’s only a few streaks of flour left.
3/4 cup (90g) all-purpose flour, 1/2 tsp fine sea salt
Spread into the prepared pan and 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. Top with a pinch of sea salt flakes and serve warm or cooled.
pinch sea salt flakes