Tuna Casserole

1/2 cup chopped onion
2-10 oz cans cream of chicken soup
1 cup milk
10 oz frozen peas
8 oz uncooked medium egg noodles
2-6 1/2 oz cans flaked tuna

Sprinkle onion in crockpot. Mix soup and milk in large bowl. Add peas, noodles and tuna. Stir well. Turn into crockpot. Cover ans cook on Low for 6-8 hours or High for 2 1/2 to 3 hours. Stir before serving.