Cook pasta according to package directions. Combine sweet potato puree, milk, salt, jalapeño, pepper, and cheese. Add cooked & drained macaroni to the mixture. Preheat broiler. Warm olive oil in a large dutch oven over medium heat. Add chorizo to pan. Cook for 4 minutes or until browned. Remove chorizo from dutch oven. Wipe it clean. Spoon sweet potato mixture into pan and sprinkle evenly with chorizo. Broil 2 minutes or until lightly browned and crisp. Sprinkle with onions and cilantro.