COMBINE MILK, CHEESE, AND BUTTER IN A SM. SAUCE PAN. OVER MED. HEAT COOK UNTIL CHEESE IS MELTED, STIRRING CONSTANTLY. ADD PEAS AND TUNA, STIR AND LET STAND.
IN SEPERATE PAN BOIL WATER, ADD NOODLES. COOK 10-12 MIN. OR UNTIL TENDER. DRAIN NOODLES. pLACE NOODLES IN A CASSEROLE DISH ADD CHEESE SAUCE WITH PEAS AND TUNA. MIX. PLACE IN OVEN AT 350 FOR 20 MIN. SERVE.