Stir together butter, sugar, and egg in a stand mixer.
In a separate bowl, combine flour, baking powder, salt, nutmeg, cinnamon, and baking soda. Slowly incorporate dry ingredients into butter mixture. Add milk and continue stirring. Fold in apples.
Divide batter into lined muffin tin.
Bake for 20 minutes. Allow to cool.
Spread a layer of caramel over tops. Frost with vanilla buttercream.
Recipe by Rachel Schultz at https://rachelschultz.com/2014/11/18/caramel-apple-cupcakes/