Select saute setting on a 6-qt. electric pressure cooker and adjust for medium heat; add oil. When oil is hot, cook and stir onion and sausage until sausage is lightly browned. Add garlic; cook 1 minute longer. , Stir in 4 cups broth, rice, salt and pepper. Lock lid and close pressure-release valve. Adjust to pressure-cook on low for 3 minutes. Allow pressure to naturally release for 10 minutes, then quick-release any remaining pressure. Rice should be tender., Select saute setting; adjust for low heat. Stir in chicken and remaining broth. Cook until chicken is heated through, about 5 minutes. If desired, sprinkle with green onions. Serve with hot sauce.