How to Make It
Preheat oven to 350°F. Cook pasta according to package directions. Drain; rinse with cold water, and drain again. Toss together pasta, turkey, and peas in a large bowl. Set aside.
Melt 3 tablespoons cold butter in a large skillet over medium-high. Add mushrooms, onion, oil, and thyme sprigs; cook, stirring occasionally, until onion is tender and mushrooms are nicely browned, 6 to 7 minutes. Remove and discard thyme sprigs. Stir in soup, milk, garlic, salt, and pepper; cook, stirring constantly, 2 minutes. Pour over pasta mixture in bowl; stir to combine. Spoon mixture into a 13- x 9-inch baking dish coated with cooking spray.
Stir together panko, Parmesan, and 1 tablespoon melted butter in a bowl; sprinkle evenly over pasta mixture in dish. Bake in preheated oven until golden brown and bubbly, 25 to 30 minutes. Sprinkle with parsley. Serve immediately.