Preheat oven to 350°F. Line cupcake trays with paper liners.
Cream butter and sugar together until smooth.
Whisk egg. Add half of the egg into creamed mixture. Mix until uniform. Add remaining egg and repeat.
Sift flour into mixture and fold together gently.
Portion batter into cupcake molds, filling about half way.
Bake cupcakes for around 20 minutes (until golden brown).
Move to wire rack for cooling.