This tuna noodle casserole is a family favorite that is filled with thick noodles, vegetables and tender chunks of tuna fish. All baked together in one pan in 30 minutes!
Preheat the oven to 375 degrees Fahrenheit. In a large pot, boil the 12 ounces wide egg noodles according to package directions, and drain and rinse.
In a medium skillet over medium-high heat, add the 1 tablespoon olive oil, 1 diced small onion, and 1 cup diced celery. Cook for 2-3 minutes until almost tender. Add in the 1 cup sliced mushrooms and continue to cook until tender. Remove from heat and add to a large bowl.
Add the 2 tablespoons butter to the skillet and whisk the ¼ cup flour until golden. Slowly whisk in the 1 ½ cups chicken broth and 2 cups whole milk. Let simmer until thickened. season with salt and pepper
In the large bowl, add the pasta, 2 (6-ounce) cans tuna fish, 1 cup thawed frozen peas, and 1 cup shredded cheddar cheese and mix. Spread the mixture in a 9x13-inch casserole dish.
In a small bowl, combine ½ cup grated parmesan, ½ cup Italian breadcrumbs, and ¼ cup melted butter. Sprinkle on top of casserole.
Bake for 25-30 minutes or until bubble and golden brown on top.