Melt the butter and dark chocolate together in a large bowl over a bain-marie. Stir occasionally. Once melted, leave to cool.
In a separate bowl, sieve the flour and cocoa powder together
In a bowl, break the eggs and add in the sugar. Mix together with a whisk until smooth and creamy. It should turn into a pale, yellow mixture.
Pour the chocolate mixture into the eggs, folding through with a spatula.
Mix in the dry ingredients and fold once again, being careful not to knock out too much of the air.
Chop up the milk chocolate into chunks and add into the mixture. Mix until fully incorporated.
Line a square tine (20x20cm) with parchment paper.
Pour the mixture into the tin and back for 20-25 minutes. If you prefer more gooey brownies bake for 15 minutes and use a toothpick to check the middle.
Allow to cool before drizzling over Joe & Seph's Chocolate Orange Caramel Sauce and Chocolate Orange Popcorn.