8 ounces dry egg noodles
3 tablespoons butter
2 tablespoons olive oil, divided
1 onion, chopped in a small dice
2 ribs celery, chopped in a small dice
2 cups mushrooms, sliced
1/4 cup dry white wine
2 teaspoons soy sauce
1/2 teaspoon salt
1/2 teaspoon ground black pepper
1/4 cup all-purpose flour
3 cups milk
2 teaspoons Dijon mustard
2 5-ounce cans tuna, drained
2 cups frozen spinach, thawed with excess water squeezed out of it
1 cup panko bread crumbs
3/4 cup Cheddar cheese, grated
Preheat oven to 375 degrees Fahrenheit and grease a 9" x 13" casserole dish.
Bring a large pot of water to a boil. When boiling, cook egg noodles according to the package directions. Drain and set aside and then wipe out the pot.
Heat butter and 1 tablespoon of olive oil in the pot over medium heat. Add onion and celery and cook, stirring occasionally until vegetables are soft, about 5 minutes. Add mushrooms and cook, stirring occasionally, about 3 to 5 minutes. Stir in white wine, soy sauce, salt and pepper, and cook until nearly all the liquid has evaporated, about 3 minutes more.
Sprinkle flour over the vegetables, stir to coat and cook for another 30 seconds.
Add the milk and mustard, stirring as you do, and cook until the sauce begins to thicken, about 2 minutes. Add tuna, spinach, and the cooked egg noodles. Cook for another 3 minutes, just until all ingredients have been warmed through. Pour into the prepared casserole dish.
Combine bread crumbs and Cheddar cheese in a small bowl with the remaining tablespoon of olive oil. Mix well and sprinkle over the tuna and vegetable mixture.
Place the casserole dish into the preheated oven and bake for 20 to 25 minutes, until the dish is bubbling throughout and the top is golden brown.