Product Recall: One SKU of Oscar Mayer Classic Wieners due to possible mislabeling. Click Here.
HEAT oven to 400ºF.
BROWN meat with onions in skillet; drain. Stir in ketchup and mustard.
SPOON into 9-inch square baking dish sprayed with cooking spray; top with remaining ingredients.
BAKE 30 to 35 min. or until casserole is heated through and potato nuggets are golden brown.