Wash your hands very well with warm water and soap.
Preheat oven to 350 degrees.
Mix ground beef, breadcrumbs, milk, egg, Worcestershire sauce, garlic and salt together in a bowl. Set aside.
In a small bowl, combine the ketchup and brown sugar.
Fill a 12-cup muffin tin with cupcake wrappers or bake directly in the muffin cups.
Spoon the ketchup mixture into the bottom of each wrapper or bottom of each muffin cup.
Scoop about ¼ cup of beef mixture into your hands and place a cheese cube into the center. Fold over the meat mixture covering the cube completely. Add the meat patty into your lined or un-lined muffin cups.
Bake about 25 minutes until an instant-read thermometer reads at least 160 degrees when inserted into the center of the meatloaf cupcake.
Remove the meatloaf cupcakes and drain off the grease. Warm up the mashed potatoes in the microwave according to the package directions.
Add a few drops of food coloring and mix well. Fill a frosting bag with mashed potatoes and decorate each top to look like creamy frosting.