So, when I set about creating an allergy-friendly shortbread recipe that my niece could indulge in this Christmas, it was quite a frustrating endeavor. Thankfully, there are some wonderful vegan spreads on the market that work quite well. My favorites are the Earth Balance vegan buttery sticks and Nuttelax spread. Both work well in this recipe. But if you are not refraining from dairy or need to make these soy-free, feel free to use conventional butter, which will make these shortbread cookies taste even better. I have deliberately chosen to use coconut sugar in this recipe, as it adds a gorgeous caramel-like quality that comes the closest to replicating the richness of butter. But if you want to make these more forgiving on the purse strings, feel free to use conventional cane sugar. The secret ingredient in this blend is the vanilla extract and lemon zest. If you want these really lemony, feel free to add more zest, But two teaspoons was juuuuust right for me.