This is trashy American comfort food and it is very fine. You can vary how rich it is by the kind of milk you use (whole, low fat, skim) and how much mayonnaise you add. Yes, mayonnaise. Do not even.
-2 cans cream of mushroom soup
-1.5 cups milk
-1/4 – 1/2 cup mayonnaise
-1 pound egg noodles, cooked until still firm, set aside
-1.5 cups frozen or fresh peas
-miscellaneous leftover veggies if you have on hand; chopped carrots are good
-Salad Supreme seasoning (McCormick’s brand in the US; otherwise celery seed, salt, pinch cayenne, orange peel, black pepper, salt, sesame seeds. Or whatever.)
2 cans albacore tuna (10-12 ounces)
The theory here is the same as for creamy macaroni and cheese—-never bake the entire casserole with noodles in it. Prepare it on the stove top then briefly broil to get a nice crumb crust on top.
Put soup in saucepan over medium low heat. Whisk in milk and several dashes Salad Supreme. Heat until it can be whisked smooth, then add peas. Return to simmer and stir, adding other veggies if you have them. Cook until peas are tender, then add tuna and mix. Remove from heat. Meanwhile, put cooked egg noodles in very large bowl or pan. After the sauce has cooled slightly, whisk in mayonnaise. Add sauce to cooked noodles and stir, thinning with milk if necessary. Adjust seasoning.
Put on oven broiler. Pour noodles into lightly greased casserole dish. Top with parmesan, Salad Supreme or paprika. Place under broiler just long enough to give a golden crust, no longer than 4 minutes.