Vanilla Rosettes Cupcakes

I made this sometime ago using a very basic buttercake recipe. I forgot exactly how many cupcakes this recipe yields, maybe 40 regular ones.

Ingredients
250 gm unsalted butter
150 gm castor sugar
2 tsp vanilla essence
6 eggs (room temperature)
200 ml fresh milk
450 gm all purpose flour
2 tsp baking powder

1. Heat oven at 180 degree celcius.
2. Sieve flour, baking powder together in a bowl.
3. Cream butter until light and add sugar, beat till it turns a shade lighter and sugar combined.
4. Add vanilla and an egg at a 30 seconds interval, alternate with 2 scoops of flour mixture.
5. Pour in milk, alternating with the rest of the flour mixture.
6. Pour batter into cupcake liners or cups. Fill only half full.
7. Bake for 10 - 15 minutes, till cake skewer comes out clean.
8. Cool completely before icing with vanilla buttercream frosting.

Recipe for frosting
125 gm butter (room temperature)
500 gm icing sugar
a little milk
2 tsp vanilla essence

1. Beat all the ingredients together taking great care not to add too much milk.
2. Consistency must be soft and creamy but does not drop off from the spoon.
3. Pipe using a medium size star nozzle.