Peel cut in half and slice onions and set aside. Place butter in 3 quart glass casserole measuring cup. Microwave at HIGH until melted, about 1 1/2 minutes. Add onion slices, tossing to coat. Cover and microwave on high 6-8 minutes or until onions are tender, stirring at least twice. Blend in broth, water, sugar, wine and pepper. Cover and microwave on HIGH until heated through about 8 minutes.