Preheat oven 350 degrees F. In a small bowl, cover dried mushrooms with hot water; set aside to soak for 30 minutes. After mushrooms have soaked, drain them, and coarsely chop. Meanwhile, prepare manicotti shells according to package directions, drain, and cool. Lightly spray an 8 by 8-inch baking pan with olive oil; set aside. Heat a nonstick pan over medium heat, and spray pan with olive oil as it is heating. Add ground turkey and brown, breaking it up to cook evenly. Drain fat from pan. Add garlic and onions and cook until onions are translucent, about 3 minutes. Add mushrooms and continue cooking for 1 to 2 minutes. Add roasted peppers and cook for about 2 minutes. Turn off the heat, and stir in the ricotta. Add salt and pepper, to taste. Transfer turkey mixture to a large resealable plastic bag. Pipe the filling into the cooled manicotti shells. Place the manicotti shells in the prepared baking dish. Top with tomato sauce and then sprinkle Parmesan over top. Fill the cooled pasta shells with the turkey mixture and Parmesan. Bake for 25 minutes. Serve immediately.
Heat olive oil in a medium saucepan over medium heat. Add garlic, onion, and dried oregano, and saute until onion is translucent. Add tomato sauce and bring to a simmer. Remove from the heat and pour over the prepared stuffed manicotti shells.