# Ingredients:
→ Pasta and Fish
01 - 12 ounces egg noodles
02 - 2 cans (5 ounces each) solid white tuna in water, drained
→ Vegetables
03 - 1 cup frozen peas, thawed
04 - 1 cup cremini or white mushrooms, sliced
05 - 1 small yellow onion, finely chopped
06 - 1 cup celery, diced
07 - 2 cloves garlic, minced
→ Sauce
08 - 3 tablespoons unsalted butter
09 - 3 tablespoons all-purpose flour
10 - 2 cups low-sodium chicken or vegetable broth
11 - 1 cup whole milk
12 - 1/2 cup sour cream
13 - 1/2 teaspoon kosher salt
14 - 1/2 teaspoon freshly ground black pepper
15 - 1/2 teaspoon Dijon mustard
→ Topping
16 - 3/4 cup panko breadcrumbs
17 - 1/2 cup grated Parmesan cheese
18 - 2 tablespoons unsalted butter, melted
19 - 2 tablespoons chopped fresh parsley (optional)
# Directions:
01 - Preheat oven to 400°F. Lightly grease a 9x13-inch baking dish.
02 - Boil egg noodles in salted water until just al dente. Drain and set aside.
03 - Melt 3 tablespoons butter in a large skillet over medium heat. Add onion and celery; cook for 3 minutes. Add mushrooms and continue cooking for 4 minutes until tender. Stir in garlic and cook for 1 minute.
04 - Sprinkle flour over vegetables and stir to combine. Gradually add broth while stirring. Add milk and simmer, stirring occasionally, until thickened, about 3 to 4 minutes.
05 - Remove skillet from heat and stir in sour cream, Dijon mustard, salt, and pepper.
06 - Gently fold in tuna, peas, and cooked noodles until evenly incorporated.
07 - Transfer mixture to prepared baking dish.
08 - In a small bowl, mix panko, Parmesan, and melted butter. Evenly sprinkle over casserole.
09 - Bake for 20 to 25 minutes until topping is golden and casserole is bubbling.
10 - Let stand for 5 minutes, garnish with parsley if desired, and serve.