Tuna casserole is the ultimate in comfort food—but when it's made with just five ingredients and updated with some pesto and fancy pasta, it's also fun to make (and eat)! This five-ingredient tuna Alfredo casserole recipe is perfect for dinner on a busy weeknight.
You could add just about any frozen, thawed vegetable to this easy updated tuna casserole recipe. Try adding peas, corn, some drained canned mushroom slices, chopped green onion, chopped cooked bell pepper, or regular onion. That's what is so nice about casseroles; they can be changed to suit your whim and what you have on hand.
When you make a casserole that has pasta in it, it's important to undercook the pasta slightly before adding it to the remaining ingredients. The pasta will continue cooking in the casserole dish in the oven and you don't want it to overcook and be mushy.
Preheat oven to 400 F. Bring a large pot of water to a boil.
Cook the pasta according to directions, taking one minute off the cooking time. When the pasta is almost al dente, drain well.
Meanwhile, combine pesto and Alfredo sauce in a medium bowl and mix to combine. Add the cooked pasta and tuna, then mix gently.
Pour the tuna mixture into a greased 2-quart glass baking dish and top with Parmesan cheese.
Bake for 15 to 20 minutes until cheese is melted and casserole is hot.