Preheat oven to 170-180C and line a cake tin with baking parchment.
Break up the dark chocolate and half the milk chocolate, into rough chunks and cut the butter into pieces.
Place the butter into a bowl and add the dark and milk chocolate chunks and bain-marie it all, mixing until it’s uniform. Take the bowl off the heat and leave it to cool.
Chop the remaining milk chocolate into small chunks (if not using chips) and set aside.
Sieve the chocolate powder, flour, nutmeg into a bowl and set aside.
Cream together the eggs, sugar and a few drops of vanilla essence until light and fluffy using an electric mixer. This will take a while, the resulting mixture should be thick and nearly twice the volume of what you started with.
Fold in the butter, chocolate mixture gently to avoid losing the air you’ve creamed in.
Fold in the flour, chocolate powder, nutmeg and most of the Picota cherries bit by bit. Mix until uniform.
Pour into the tin and sprinkle the chips and remaining cherries on top.
Place in the oven and cook for 30-40 minutes. The centre of the brownie should no longer wobble when you gently shake the cake tin. If it does, it needs a few more minutes. Cool for about 20 minutes. Then cut into squares.