Cook manicotti according to package directions. In a small bowl, combine the chicken, 1/4 cup salsa, ricotta cheese, olives, parsley, pimientos, green onion, garlic and pepper sauce. Drain manicotti; fill with chicken mixture.
Spread 1/4 cup salsa in an 8-in. square baking dish coated with cooking spray. Top with manicotti shells and the remaining 1/2 cup salsa.
Cover and bake at 400° for 20 minutes. Uncover; sprinkle with Monterey Jack cheese and bake until cheese is melted and filling is heated through, 5-10 minutes longer.