Preheat oven to 350°F (175°C). Line a muffin tin with cupcake liners.
In a large bowl, cream butter and sugars until fluffy.
Add eggs one at a time, beating well after each. Mix in vanilla.
In a separate bowl, whisk flour, baking powder, and salt.
Add dry ingredients to wet, alternating with milk, mixing until just combined.
Divide batter evenly into liners and bake for 16–18 minutes, or until a toothpick comes out clean.
Let cupcakes cool completely before decorating.
For frosting, beat butter until creamy. Add powdered sugar and vanilla. Add milk until desired consistency is reached.
Frost each cupcake with a fluffy swirl.
Decorate with marshmallow ears (dipped in pink sugar), chocolate chip eyes, and candy noses. Optional: Sprinkle coconut for a fur effect.
Chill for 10 minutes to set decorations if needed.