Melt chocolate with coffee and butter in a bowl.
Whisk eggs and sugar till creamy. Add in flour with baking powder and then stir in the chocolate coffee mixture.
Stir in the chopped nuts.
Transfer the mixture into a square tin and bake in oven gas 3 or 140C for 45 minutes. When cooked, leave to cool.
Melt chocolate, butter and coffee in a pan.
Stir in the Ameretto liqueur.
Place a slice of Brownie on a warm plate. Spoon over with warm Chocolate Coffee sauce. Decorate with whipped cream and a Physalis.