01 -
Preheat oven to 175°C and grease a 23 x 33 cm baking dish.
02 -
In a large mixing bowl, whisk together flour, cocoa powder, baking powder, and granulated sugar until well blended.
03 -
In a separate bowl, whisk together melted butter, eggs, and vanilla extract until smooth and fully emulsified.
04 -
Pour the butter-egg mixture into the dry ingredients, stirring gently until just combined and no pockets of flour remain. Avoid overmixing.
05 -
Spread the batter evenly in the prepared baking dish. Bake for 25–30 minutes, or until a toothpick inserted into the centre comes out with moist crumbs.
06 -
Remove from oven, sprinkle mini marshmallows and chopped pecans or walnuts evenly over the cake. Return to oven for 5 minutes, until marshmallows are golden and slightly melted.
07 -
Melt chocolate chips and butter together in a heatproof bowl set over simmering water, stirring until smooth.
08 -
Drizzle warm chocolate glaze over the marshmallow-topped cake. Allow to cool slightly before slicing and serving.