>> source: https://www.bbcgoodfood.com/recipes/best-ever-chocolate-brownies-recipe
>> servings: 16
>> time: 1 hour

Cut @unsalted butter{185%g} into small cubes and tip into a #medium bowl{}. Break @dark chocolate{185%g} into small pieces and drop into the bowl.

Fill a #small saucepan{} about a quarter full with hot water, then sit the bowl on top so it rests on the rim of the pan, not touching the water. Put over a low heat until the butter and chocolate have melted, stirring occasionally to mix them. Remove the bowl from the pan and leave to cool to room temperature.

Preheat #oven{} to 180°C/160°C fan. Line a #shallow 20cm square tin{} with non-stick baking parchment.

Sift @plain flour{85%g} and @cocoa powder{40%g} into a #sieve{} held over a #medium bowl{}. Tap and shake so they run through together.

Chop @white chocolate{50%g} and @milk chocolate{50%g} into chunks.

Break @eggs{3} into a #large bowl{} and tip in @golden caster sugar{275%g}. With an #electric mixer{} on maximum speed, whisk the eggs and sugar until thick, creamy, and about double the original volume, about ~{3%minutes} to ~{8%minutes}.

Pour the cooled chocolate mixture over the eggy mousse, then gently fold together with a #rubber spatula{} in a figure of eight motion until the colour is a mottled dark brown.

Hold the sieve over the bowl and resift the cocoa and flour mixture, shaking from side to side to cover the top evenly. Gently fold in using the same figure of eight action.

Stir in the white and milk chocolate chunks until dotted throughout.

Pour the mixture into the prepared tin and level the top. Bake for ~{25%minutes} to ~{30%minutes}, until the top has a shiny papery crust and the sides are just beginning to come away from the tin.

Leave in the tin until completely cold, then cut into squares or triangles.