sugar substitute, such as splenda (or granulated sugar) • butter, softened • egg yolks (or equivalent of egg substitute) • sour cream • baking soda • gluten-free flour (or reg flour) • xanthum gum (if using reg flour or a gluten-free flour mixture that already includes this ingredient, dont need to use this ingredient) • poppy seeds • vanilla, divided • egg whites (or equivalent of egg substitute), stiffly beaten • powdered sugar • soy milk (or milk of your choice) •