Steps

• Preheat your oven to 400F and move the rack to the middle position.
• Add the potatoes to a greased 9x13 casserole dish.
• Add the beef and onions to a skillet and cook, breaking the meat up with your spoon as you go along, until browned (about 8-10 minutes). Drain excess fat if needed.
• To the skillet, add in the garlic and frozen mixed vegetables and cook for another 2-3 minutes, stirring often. Season with some salt & pepper and transfer the mixture to the casserole dish.
• In a medium prep bowl, mix the cream of mushroom soup, milk, sour cream, Worcestershire sauce, Italian seasoning, and half of the cheddar cheese together.
• Pour the sauce mixture over top of the beef and potatoes, then stir and arrange it in an even layer.
• Cover the casserole tightly with foil and bake for 45 minutes.
• Take the foil off, sprinkle the remaining cheese on top, and bake uncovered for another 10-15 minutes or until the cheese has melted and the potatoes are tender.
• Let it sit for 5-10 minutes prior to serving, then season with extra salt & pepper as needed.