Sift or whisk cake flour, baking powder, salt and ground nutmeg.
In large mixing bowl, cream butter and sugar until fluffy, around 1-2 minutes.
Mix in beaten egg.
Alternate adding dry ingredients with milk, starting and ending with dry ingredients and only mixing batter until combined.
In small mixing bowl, mash half of the diced strawberries with a fork. Fold in the mashed strawberries to the batter along with the remainder of the diced strawberries.
Line muffin tin with muffin or cupcake liners. Fill each liner 2/3 full with batter. Sprinkle top of each muffin with 1/2 tablespoon of sugar.
Bake at 400°F for 15-18 minutes, or until a toothpick comes out of the center clean.