To roast sweet potato: Preheat oven to 375 degrees F. Line a small baking sheet with parchment paper. Use a fork to poke holes all over two medium sweet potatoes, then place on the baking sheet. Bake for 45 mins-1 hour until sweet potatoes are easily pierced with a fork. Allow to cool, then remove skins and mash.
To make vegan: Instead of an egg, use a flax egg (1 tablespoon flaxseed meal + 3 tablespoons water). Also make sure to use oil instead of butter.
To make gluten free: Use a gluten free oat flour. Or make your own oat flour by blending gluten free oats until they resemble flour.