Mix ground beef, saltine crackers, onion, bell pepper, egg, BBQ sauce, Ranch Dressing, Worcestershire sauce, garlic, black pepper and seasoned salt in a bowl.
Stir ketchup, brown sugar in a bowl. Spoon ketchup mixture into the bottom of each muffin cup in a 6-cup muffin tin.
Fill the muffin cups with beef mixture, leaving 1⁄2 inch space on the top.
Bake in the preheated oven until no longer pink in the center, approximately 30 minutes.
An instant-read thermometer inserted into the center should read at least 160 degrees.
Drain fat from muffin cups.
Top each ‘cupcake’ with mashed potatoes and cheddar cheese.
Continue baking until cheese is melted, approximately 10 minutes.