Fill a 4.5 quart pan about two-thirds full of water, add 1 tsp salt per quart of water, and bring to a rapid boil. Add noodles and boil until al dente.
Meanwhile, open a 7 oz can of tuna, drain it, and break tuna into flakes. Mix with cream of mushroom soup and 1/2 cup milk.
Open 10 oz package of frozen peas and empty into colander. When noodles are done, drain them through peas in colander to thaw peas.