There's something fishy going on... and it's this tempting tuna casserole that includes spaghetti, spinach and pimientos. It's as easy as they come. Seafood and pasta swim together in one super savory dish!
Combine spaghetti, spinach and remaining ingredients, reserving some cheese to sprinkle on top. Cook in covered casserole in 350-degree oven until cheese bubbles. May be prepared a day ahead.