Mix in 3/4 of the bag of chips. In a greased baking dish combine tuna, soup, and up to 1 cup of milk (you do not want mixture watery), butter and thawed peas. Pop into preheated 350º oven and bake, uncovered, for 25 minutes. Spray a 2 1/2 quart baking dish or 13 x 9 pan and pour and spoon mixture into dish. Sprinkle top with second cup of cheese. Top with 1 cup crushed potato chips and bake 5 minutes longer. Sprinkle remaining chips across top. Best Tuna Casserole is the absolute best, easy, tuna casserole recipe around! Full of tuna, cheese, peas, a creamy sauce and topped with potato chips! I know I say everything is my favorite food around here, but, you guys, tuna casserole is my all-time most fave go-to comfort food! Flake tuna into small pieces. Bake in 350 degree oven until chips are brown and casserole is bubbly. cans tuna, drained 1 can cream of mushroom soup 1 10 oz bag Guy's Plain Potato Chips, crushed 1 Cup frozen peas, thawed (if you like peas) 3 T butter or margarine 1 Cup milk Directions Flake tuna into small pieces. Ingredients 2 7 oz.