To prepare a cheesy tuna and zucchini noodle casserole recipe, you'll first need to prepare your ingredients. You will need: 12 cup shredded cheddar cheese, 2 tablespoons mayonnaise, 1 tablespoon sour cream, and 1 teaspoon kosher salt. Mix the ingredients together until the cheese is fully melted. Pour the mixture into the bottom of an 8-inch-square casserole dish. Bake the casserole for 35 to 40 minutes, or until it's bubbly and the top is golden brown.