Ingredients

• 6 ounces egg noodles, preferably whole-wheat (4 1/2 cups dry)

• 3 tablespoons butter

• 2 tablespoons extra-virgin olive oil, divided

• 1 cup finely chopped onion

• ½ cup finely chopped celery

• 10 ounces mushrooms, sliced

• 3 tablespoons dry sherry

• 2 teaspoons reduced-sodium soy sauce

• ½ teaspoon kosher salt

• ½ teaspoon ground pepper

• ¼ cup white whole-wheat flour or all-purpose flour

• 2 cups low-sodium chicken broth, divided

• 1 cup reduced-fat milk

• 2 teaspoons Dijon mustard

• 2 5-ounce cans chunk light tuna in olive oil (see Tips), drained and flaked

• 10 cups baby spinach or 4 cups frozen chopped spinach (thawed)

• 1 cup coarse fresh breadcrumbs (see Tips), preferably whole-wheat

• ¾ cup grated aged Cheddar cheese