Preheat your oven to 180℃.
Grate your sweet potato, 5 seconds, speed 5. Place in a lined or fine sieve and press to remove the moisture (roughly)
Melt your butter or oil (if required) 1 minute, temp 90, speed 3.
Add back the sweet potato, sweetener, eggs, vanilla, and mix to combine 10 seconds, speed 4.
Add the cacao, bicarb and baking powder and mix 5 seconds, speed 3.
Add the coconut flour and mix 5 seconds, speed 3. Coconut flour absorbs a lot of liquid so you should only need the two tablespoons. Your batter should be the consistency of a thick, airy (cake like) batter. Let it sit for a minute and if it still seems a little wet, add more coconut flour teaspoon by teaspoon.
Continue from point 6 above.