Grandma EsteeS Tuna Casserole

Ingredients

• 14 c chopped onion
• 1 Tbsp margarine or butter
• 2 cans cream of mushroom soup
• 12 c shredded processed cheese
• 18 tsp dry mustard
• 1 7 oz can tuna drained and flaked
• 2 c cooked macaroni
• 12 c cooked peas
• 12 c potato chips

Directions

1. In saucepan cook onion in butter until tender
2. Blend in soup cheese and seasoning
3. Heat until cheese melts
4. Combine with tuna macaroni and peas
5. Pour into 1 12-quart casserole dish
6. Crumble potato chips on top
7. Bake in moderate oven until nicely browned and bubbling