It's Tea Time with Banana Chocolate Cupcakes.

This is a European recipe, so I converted the grams and ounces to cups and mls. I have European measuring utensils appropriate for this recipe, so if you have American measuring utensils then half a cup for me is 118mls whereas half a cup for you is 125mls. This recipe is written in my measurements with yours in the brackets.  

CUPCAKES
   118 mls (half cup) butter
   177 mls (3/4 cup) sugar
   2 eggs
   2 large mashed ripe bananas
   1 tsp baking soda
   2 tbsp boiling milk
   1 tsp baking powder
   236 mls (1 cup) flour

Cream butter and sugar until light and fluffy. Add eggs one at a time. Mix in mashed banana. Add baking soda that has been dissolved in the boiled milk. Mix in sifted flour and baking powder. Don't over beat batter!
Bake at 325 F for 18-25 minutes. Until they are light golden on top and a toothpick comes out clean.

    

CHOCOLATE FROSTING
   148 mls (2/3 cup) unsalted softened butter
   207 mls (3/4 + 1/8 cup [or 5/8 cup]) confectioners sugar
   29 mls (1/8 cup) cocoa powder
   1 tbsp lukewarm milk
   1 tsp vanilla

Cream butter and sift in the confectioners sugar and cocoa powder. Add the milk and vanilla. If it needs more milk, add up to 1 more teaspoon of lukewarm milk. Mix until well incorporated. If it looks curdled, add more confectioners sugar.