If you didn't have any instructions, how would you duplicate this cupcake? Suggest a method and then click on the link to see Kurryleaves's clever approach. Did you guess correctly?
color some cake batter red, put it in a heart candy mold and freeze it, after it is frozen drop it in the cupcake batter and cook. If you do not have a mold then freeze it and before it get hard, mold it like clay into heart, then freeze it more