1Remove excess fat from pork. Sprinkle pork with salt and pepper. In 12-inch skillet, heat oil over medium-high heat. Add pork; cook about 5 minutes, turning once, until brown.
2Place pork in 3 1/2- to 4-quart slow cooker. Sprinkle onion over pork. Add pasta sauce.
3Cover; cook on Low heat setting 4 to 6 hours.
4Place orzo on platter. Top with pork and sauce. Sprinkle with cheese.