Triple Chocolate Cake

Chocolate brownies (18cm mold)
20g dark chocolate
20g butter
30ml milk (2 tbsp)
legg
30g sugar
a pinch of salt
30g all purpose flour
8g cocoa powder
1/2 tsp baking powder
30g hazelnuts (optional but better)
Bake it 180C for 20 -22 minutes, cool down and cut into a 16cm circle
Whipped cream: (keep it cold all the time)
300g cold heavy cream
8g powdered sugar