Peel onions and cut crosswise into 1/2-inch thick slices. Remove centers of slices to leave 1/4-inch thick rings. (Reserve centers and end pieces for other uses. They will keep in a plastic bag for several days if refrigerated.) Prepare batter by combining flour, cornmeal, oat bran, sugar, baking powder and soda. Beat buttermilk, egg whites and oil. Stir into dry ingredients to make a relatively smooth batter. Heat a lightly oiled griddle to 350 degrees. Place onion rings on griddle. Spoon batter into each ring just to fill. Cook until bottom sides begin to brown. Turn and cook until other sides are done. Serve hot as bread or vegetable side dish. Yields 4-6 servings. FROM SOME NEWSPAPER ARTICLE From a collection of my mothers (Judy Hosey) recipe box which contained lots of her favorite recipes, clippings, etc. Downloaded from Glens MM Recipe Archive, G Internet.