With béchamel and canned mushrooms.
From a box sold in Lyndhurst, New Jersey.
Mother’s Tunafish Casserole
1 can tuna fish
2 hard boiled eggs
2 cups white sauce
1 medium size can mushrooms
Buttered bread cubes
Put in casserole a layer of tuna fish, mushrooms, and eggs and pour white sauce thoroughly through it. Put buttered bread cubes on top and bake in oven at 300 deg. for about 45 minutes.