Tater-Topped Casserole

From Kraft Foods: http://www.kraftfoods.com/kf/recipes/tater-topped-casserole-111257.aspx

1 lb. ground beef
1 small onion, finely chopped
1 can (10-3/4 oz.) condensed cream of mushroom soup
1/4 cup milk
1 cup frozen mixed vegetables
1 cup KRAFT Shredded Cheddar Cheese
1 lb. (1/2 of 32-oz. pkg.) frozen bite-size seasoned potato nuggets

HEAT oven to 375ºF. Brown meat with onions in large skillet, stirring occasionally; drain. Spoon into 2-qt. casserole dish. MIX soup and milk; pour over meat mixture. Top with layers of vegetables, cheese and potatoes. BAKE 45 min. or until potatoes are golden brown and casserole is heated through.