Spaghetti Beef Casserole
["1 lb. spaghetti twists", "2 lb. ground beef", "1/2 c. onion, chopped", "1 Tbsp. shortening (optional)", "2 (16 oz.) cans tomato sauce", "1 Tbsp. chili powder", "1 tsp. salt", "1/4 tsp. pepper", "1 1/2 lb. Velveeta cheese, cubed"]
["Preheat oven to 350\u00b0. Grease a 9 x 13-inch casserole dish with Pam. Cook spaghetti twists according to package directions and drain."]
["ground beef", "onion", "shortening", "tomato sauce", "chili powder", "salt", "pepper", "Velveeta cheese"]