Trim tough membranes and veins from liver. Cut into thin strips 2 to 3 inches long; set aside.
In a 10-inch skillet over medium heat, sauté onions in 1 tablespoon of the margarine 15 minutes or until browned; remove. Increase heat to medium-high. Heat 1 tablespoon of the margarine. Sauté half of the liver 30 seconds or until no longer pink. Remove liver from skillet. Repeat with remaining margarine and liver.
Return liver and onions to skillet. Sprinkle with parsley, vinegar, and sage. Toss to heat through. Serve immediately.
Venetian Liver and Onions comes from the Cook'n Deluxe collection. Click here to order this CD or download this brand-name recipe set right now!