Biscuits: Preheat the oven to 425℉. Microwave the sweet potato until very tender. Open with a knife and allow to steam until cool enough to handle.
While the sweet potato cools, mix coconut flour, arrowroot starch, gelatin, garlic powder, salt, and baking soda. Add the vinegar, oil and inside of the sweet potato and smash with a fork to bring it all together.
Turn the dough out onto a clean counter (or use parchment paper for easy clean-up). Fold over a few times to get it into a 1-2 inch thick layer. Roll into a flat little block and cut 6 to 8 biscuits with a glass or biscuit cutter…or just shape by hand. Let’s not be too precious here.
Filling: Make a mirepoix in a large oven-safe Dutch oven or pan: olive oil, onion, celery, and carrot. Sauté over medium heat until the onion is translucent, about 5 minutes. Add the chicken, stirring occasionally to brown. Gradually, add the garlic, salt, sage, and thyme, stirring and resting between each new addition (this is called layering). Lastly, add the sodium free stock along with the arrowroot starch. Stir right away and simmer to thicken, about 10 minutes. Using tongs, carefully transfer the cooked chicken to a plate and shred into small pieces then return it to the pot. Add the coconut milk, if desired.
Bake: Arrange the biscuits on top of the filling. Brush with coconut milk for extra color. Bake for 20 minutes, until hot, bubbly, and biscuits are cooked through. Let rest for 10 minutes before serving and season with salt, lemon, or chives to taste.