Granulated white sugar is important in this recipe; substituting another sweetener won’t give you quite the right texture. However, if strict veganism is important to you, make sure to use a granulated sugar that is labeled as such. Cane sugar can involve bone char in the refining process, so some folks don’t consider it vegan. Sugar derived from beets, on the other hand, is always vegan, and that’s what we use at Tandem. At Tandem we mix individual flour blends for each recipe, but most folks don’t keep this many flours and starches on hand at home. We have experimented with substituting store-bought gluten-free flour blends in this recipe with mixed results. If you decide to try a store-bought blend, look for one that is vegan, with no dairy products (including whey) or eggs, and that includes xanthan gum.