Preheat oven to 375ºF. Lightly grease a 12-cup muffin tin and set aside.
In a large mixing bowl, combine sweet potato, avocado, syrup, flaxseed meal, water and non-dairy milk. Beat until smooth. Set aside and let rest for 5 minutes.
Once rested, add in flours, baking powder, salt and cinnamon to the bowl with the wet ingredients. Mix until just incorporated. If the batter feels dry, add more milk 1 tablespoon at a time until the batter resembles a thick pancake batter. Fold in chocolate chips.
Spoon muffin mixture into prepared pan, filling each cup ¾ of the way full.
Bake on center rack for 18 - 19 minutes, until a toothpick inserted into the center comes out clean.
Let cool in the pan for 3 minutes, then transfer to a wire rack and cool completely.
I enjoyed these muffins slightly warm, so reheat if desired, or enjoy them as is!