Egg, nondairy and sugar substitution in biscotti/mandelbrot
I know that the use of eggs and sugar helps to make these taste delicious. As a nondairy and sweetener alternative, has anyone had success using silken/soft tofu as an egg substitute (or an egg-replacer product), and stevia or agave in this baked good without compromising its texture and taste? If egg is not used, I'd think there would have to be some other ingredient added to provide the richness imparted by the egg not replaced by the tofu? Yes, if these alternative ingredients are successfully used, I can eat these guys with abandon! (edited after initial subject title misconveyed eggs as dairy. Sorry for the misidentification! While doing a substitution for eggs, I thought of leaving out dairy in general.)
I don't have a suggestion -- just a mention that the eggs and sugar are part of the structure in these two products, thus flavor isn't your only issue here...
Tofu as an egg substitute is for when you need the body and texture of scrambled egg. It won't do the work of egg as a binder or levener, which is how you need it in a biscotti. You can probably substitute with arrowroot or cornstarch, which are usually a principal ingredient in powdered egg substitutes, and add a little extra baking powder or baking soda. Some applesauce usually helps with the texture of eggless baked goods, too, and adds a mild sweetness.
As a main sweetener, I would go with maple syrup, agave nectar (nectar, not syrup), brown rice syrup or barley malt rather than stevia, because they provide a certain caramelized flavor that stevia doesn't have.
Nonna's Italian Kitchen, a vegan Italian cookbook, has a great vegan biscotti recipe, but it does call for white sugar. http://www.food.com/recipe/vegan-almo... . If you want to avoid cane sugar all together, I'd try a recipe like that with crystallized maple sugar -- maybe just 1 cup rather than the 1.5 cups Nonna calls for. If you're just avoiding refined sugar, maybe go with raw demerara sugar and just sub it one for one (although that recipe is pretty sweet so I think I'd still only use one or three-quarters cup).
Here's a Vegetarian Times recipe that looks pretty good, too: http://www.vegetariantimes.com/recipe...