Shells & Cheese Cheeseburger Mac

1 lb. ground beef
2 1/2 cups milk
1/4 cup ketchup
2Tbsp. yellow mustard
1 Tbsp onion powder
1 12oz. pkg Velveeta Shells & Cheese Dinner (or shell pasta & your favorite cheese)
1/4 cup sour cream
1 cup chopped tomatoes (about 1 large)
1/4 cup sliced green onions

Brown meat in large skillet; drain. Return meat to skillet.

Add milk, ketchup, mustard, and onion powder; mix well. Bring to boil. Stir in shell pasta; return to boil. Reduce heat to medium-low; cover. Simmer 10 min or until pasta is tender.

Stir in cheese sauce (if using the one from the package, I only use about 1/4-1/3) and sour cream until well blended. Add tomatoes & onions; mix well.