1.Preheat oven to 350° F. Line muffin pan with 12 cupcake liners.
2.In large skillet, brown SPAM® until golden. Drain on paper towel.
3.In large bowl, combine flour, baking powder, sugar and salt. Add SPAM®, reserving Â¼ cup; stir until combined.
4.In medium bowl, whisk melted butter, milk, eggs and vanilla together. Add to flour mixture. Stir until combined. Do not over-mix.
5.Spoon batter into each cupcake liner. Bake 20 to 25 minutes or until cooked. Let stand in pan 5 minutes before removing to wire rack to cool.
6.Mash potatoes until smooth. Add butter and stir with fork until butter is melted and potatoes are smooth. Stir in powdered sugar. Spoon mixture into a piping bag. Pipe potato mixture onto cakes. Sprinkle with reserved SPAM®.