This recipe comes from Jodee Linta in AZ. We taught in rooms next door to each other for years. Here's what she says about these sandwiches:

"This recipe was given to Mother during "The War" when aluminum foil wasn't heard of. She wrapped the buns in waxed paper and then heated them in the oven. You could smell the wax melting and this added to the flavor! Now I use foil or if I'm in a hurry I used waxed paper and pop them in the microwave."

Recipe comments are Jodee's.

Hearty Sandwiches

1 can Spam, coarsely grated
1 medium onion, grated
Cheddar cheese, grated, to taste (I just use a "chunk" probably 1/3 to 1/2 pound)
Mix all together with one small can of tomato paste

Spread on hamburger or hot dog buns, wrap in foil or waxed paper and heat.