# What You Need:
→ Pasta
01 - 12 ounces wide egg noodles
→ Sauce
02 - 2 tablespoons unsalted butter
03 - 1 small yellow onion, finely chopped
04 - 2 cloves garlic, minced
05 - 3 tablespoons all-purpose flour
06 - 2 cups whole milk
07 - 1 cup low-sodium chicken or vegetable broth
08 - 1/2 cup sour cream
09 - 1/2 teaspoon salt
10 - 1/2 teaspoon ground black pepper
11 - 1/2 teaspoon dried thyme
12 - 1/2 teaspoon dried parsley
→ Filling
13 - 2 cans (5 ounces each) solid white tuna in water, drained and flaked
14 - 1 cup frozen peas, thawed
15 - 1 cup sliced white mushrooms (optional)
16 - 1 cup shredded cheddar cheese
→ Topping
17 - 1 1/2 cups store-bought crispy fried onions
# How To Make:
01 - Preheat oven to 375°F and lightly grease a 9x13-inch baking dish.
02 - Bring a large pot of salted water to a boil and cook egg noodles according to package instructions until al dente. Drain and set aside.
03 - Melt butter in a large skillet over medium heat. Add chopped onion and cook until softened, about 3 minutes, then add garlic and cook for 1 more minute.
04 - Sprinkle flour over the onion and garlic mixture, stirring constantly for 1 minute to cook the flour fully.
05 - Gradually whisk in whole milk and broth, cooking until the sauce thickens, approximately 3 to 4 minutes.
06 - Remove from heat and stir in sour cream, salt, pepper, thyme, and parsley until smooth.
07 - Incorporate drained tuna, peas, mushrooms (if using), and shredded cheddar cheese into the sauce, mixing until evenly combined.
08 - Gently fold cooked noodles into the sauce mixture until fully incorporated.
09 - Transfer the mixture into the prepared baking dish, spreading it evenly.
10 - Evenly sprinkle the crispy fried onions over the top of the casserole.
11 - Bake uncovered for 25 to 30 minutes until the casserole is bubbling and the topping is golden brown.
12 - Allow the casserole to rest for 5 minutes before serving.
