Microwave Chicken Or Turkey Tetrazzini
["1 (7 oz.) pkg. spaghetti", "1/4 c. butter or margarine", "1 (4 oz.) can sliced mushrooms, drained", "1 small onion, chopped", "1 1/2 tsp. fresh lemon juice", "1/3 c. all-purpose flour", "1 tsp. salt", "1/2 tsp. paprika (for casserole) and 1/2 tsp. paprika (for top of casserole)", "2 c. turkey or chicken broth", "1/2 c. half and half or milk", "2 1/2 c. cooked and shredded chicken or turkey", "1/4 c. grated Parmesan cheese and 1/2 c. grated Velveeta (for top)", "1 c. grated Velveeta cheese (for casserole)"]
["Microwave spaghetti in 6 to 7 cups very hot water with 1/2 teaspoon salt and 1 tablespoon oil in a 13 x 9 x 2-inch dish for 9 minutes or cook on top of stove per package directions.", "Drain spaghetti and place in a 13 x 9 x 2-inch dish sprayed with Pam butter flavored cooking spray."]
["spaghetti", "butter", "mushrooms", "onion", "lemon juice", "all-purpose", "salt", "paprika", "turkey", "milk", "chicken", "Parmesan cheese", "Velveeta cheese"]