here's a good way. and guys dont knock it until u try it. cook the tuna in cream of mushroom soup. once done, spread over rice. mmmmmm. havent ate this in a while though but i used to love it.
I throw a can of tuna in a salad, add a bit of olive oil, lemon, and oregano, and it tastes pretty decent, and I'm not a nutrionist, so I'm not sure how much fat the olive oil adds, so check that out before you try this.
Lately I've been mixing it with super hot Salsa, along with alot of hot pepper. Its so damn spicey that I can hardly to taste the tuna. Also makes drinking a gallon of water a day easier when your mouth is on fire.