Posted for Zaar World Tour 2005. Pickled onions are served alongside meat dishes all over Mexico, but you can serve them with anything you want, like me when I make this recipe! Will last in the refrigerator for 2-3 weeks. The lime juice, zest and grapefruit make something called sour orange juice. I've never heard of it, can't buy it in the store and I wouldn't want to experiment with regular orange juice to make it! The beet juice is used to turn the onions red(der). Serving size is a guess. Chilling time is included in cooking time. From a special issue of Saveur, The Best of Tex-Mex Cooking.