In a large skillet, cook beef and onion over medium heat until no longer pink, drain. Stir in corn, peas, ketchup, worcestershire sauce and garlic. Reduce heat; cover and simmer for 5 mins.
Meanwhile, in a small bowl, dissolve bouillion cube in water. combine flour in sour cream till smooth, add to bouillion. Bring to a boil, then reduce heat. Spread the mashed potatoeson top, sprinkle with cheese. cover and cook till potatoes are heated through and cheese is melted.