If you don’t have an electronic mixer, you can also mash the butter and sugar together using a wooden spoon.
If you don’t have an electronic mixer, you can stir the egg into the batter using a spoon.
Continue using a spoon if you don’t have an electronic mixer.
The size of your cake balls is up to you. There are no strict rules to follow regarding size.
If you prefer a chocolate flavor, you can use chocolate candy melts instead.