Chocolate Cobbler

INGREDIENTS

1 c flour
2 tsp baking powder
1/2 tsp salt
2/3 c sugar
1 1/2 tbsp cocoa
2 tbsp butter melted
1/2 c milk
1 tsp vanilla
1/2 c chopped walnuts optional
Topping
1/4 c sugar
1/2 c brown sugar
1/4 tsp salt
1 tbsp cocoa
1 c water boiling