Preheat oven to 350 degrees F/180 degrees C.. Line or grease a 12 count medium sized cupcake pan.
In the bowl of your electric mixer, beat butter and sugar until light and fluffy, 3 - 5 minutes. Beat in eggs , one at a time, mixing well after each addition. Then beat in the vanilla.
In a small bowl, combine the flour, baking powder and salt.
Add about 1/2 of the flour to the batter and stir to incorporate. Then add the milk and stir in and then finally the remaining flour.
Evenly divide the batter between the 12 muffin cups. Bake for 15-18 minutes or until a toothpick comes out clean.
Remove from oven and leave to cool completely on a wire rack.
Make the frosting in the bowl of your electric mixer. Add the butter and beat until smooth, about 1 - 2 minutes. Whisk in the vanilla and then add the powdered sugar. Mix on high for about 2 minutes. Add the cream, one tablespoon at a time, mixing well after each addition. Continue to mix on high speed for about 5 minutes until the frosting is light and fluffy. If needed, add one more tablespoon of cream
You can pipe the frosting on the cupcakes or spread it on with a butter knife. Decorate how you like.
Best served the day they are made but will keep up to two days in an airtight container.