Preheat the oven to 375°F (190°C).
In a skillet over medium heat, cook ground beef with chopped onions and garlic until browned. Drain excess fat.
Stir in salt, pepper, Worcestershire sauce, ketchup, mustard, and cream of mushroom soup. Let simmer for 2–3 minutes.
Spread the beef mixture evenly into a greased casserole dish.
Sprinkle shredded cheddar cheese over the beef layer.
Top with a single layer of frozen tater tots.
Bake uncovered for 35–40 minutes, or until tots are golden brown and crisp.
Garnish with chopped pickles and green onions, if desired. Serve hot.