Stir corn meal, sugar, soda and salt together. Place onion in a small bowl. Add egg and buttermilk and beat until frothy. Pour all at once into the meal and stir lightly to mix. Add just enough of the cold water to make dough a good dropping. The dough should hold its shape in the spoon. Drop by tablespoonfuls into hot oil (about 350 to 360°) in deep fat fryer for about 2 minutes or until evenly browned, turning to keep all sides evenly browned. Makes about 2 dozen.