BRAISED ONIONS-Cooking with Onions

1tsp-unsalted butter 2tsp-frozen pineapple juice-concentrate 2 large red onions-cut into quarters 1 tsp-white wine vinegar 1/8-salt Ground Black Pepper In a large sauce pan over a medium heat,melt the butter.Add the onions and cook,stiring to separate them into pieces,for 5 minutes,or until they begin to soften.Stir in the pineapple juice concentrate,vinegar,and salt.Partially cover,reduce heat to low,and cook for 10 to 15 minutes,or until the onions are tender.Season to taste with the pepper. Makes 4 servings