Step 1

Bring a large pot of water to a boil. Cook noodles until just tender, 6 to 8 minutes or according to package directions. Drain and rinse.

Step 2

Position rack in upper third of oven and preheat broiler.

Step 3

Meanwhile, heat oil in a large ovenproof skillet over medium-high heat. Add onion, mushrooms and salt and cook, stirring often, until the onion is softened but not browned, about 5 minutes. Add wine and cook until evaporated, 4 to 5 minutes. Sprinkle flour over the vegetables; stir to coat. Add milk and pepper and bring to a simmer, stirring constantly. Stir in tuna, peas and 1/2 cup Parmesan until evenly incorporated. Then, stir in the noodles (the pan will be very full). Remove from the heat.

Step 4

Sprinkle the casserole with breadcrumbs and the remaining 1/2 cup Parmesan. Broil until bubbly and lightly browned on top, 3 to 4 minutes.