Best Tuna Noodle Casserole from Scratch

Ingredients

• 2 tunas steaks , 5 ounce
• 8 ounces fettuccine noodles
• 6 tablespoons butter , divided
• 1 medium onion , diced
• 6 ounces sliced portobello mushrooms
• 0.25 cups flour
• 2.75 cups milk
• 1 teaspoon chicken bouillon concentrate , such as Better than Bouillon®
• 0.5 teaspoons adobo seasoning
• 0.25 teaspoons black pepper
• 0.25 cups grated Parmesan cheese
• 4 slices bread , torn into small pieces

Instructions

1. 1

   Preheat the oven to 350 degrees F (175 degrees C). Lightly oil an ovenproof skillet and an 8x12-inch casserole dish.

2. 2

   Place tuna in the prepared skillet and bake in the preheated oven until fish flakes easily with a fork, 8 to 10 minutes.

3. 3

   Fill a large saucepan with lightly salted water and bring to a rolling boil. Cook fettuccine at a boil until tender yet firm to the bite, about 8 minutes. Drain and set aside.

4. 4

   Remove tuna from the oven; leave oven on.

5. 5

   Meanwhile, melt 3 tablespoons butter in a saucepan over medium heat. Cook onion and mushrooms until softened, stirring occasionally, 5 to 7 minutes. Stir in flour until blended. Add milk, bouillon concentrate, adobo seasoning, and black pepper. Cook, stirring constantly, until mixture is slightly thickened, about 5 minutes more. Remove sauce from heat and stir in Parmesan cheese.

6. 6

   Place remaining butter in a medium-sized microwave-safe bowl and heat in the microwave until melted, about 30 seconds. Stir bread crumbs into melted butter and set aside.

7. 7

   Add cooked fettuccine and flaked tuna to the cheese sauce and toss to combine. Transfer noodle mixture to the prepared casserole dish and top with torn bread.

8. 8

   Bake in the hot oven until golden brown, about 20 minutes.