See recipe video below for guidance! You'll be adding in the cocoa powder along with the baking powder.
Preheat oven to 390°F/200°C. Grease and dust with cocoa powder a donut pan.
Whisk together in a medium bowl almond flour, coconut flour, psyllium husk and xanthan gum. Set aside.
Heat up water, butter, sweetener and salt in medium pot (or Dutch oven) until it just begins to simmer. Lower heat to low and add in flour mixture, mixing constantly to incorporate. Continue to cook and stir until the dough pulls away from the pan and forms into a ball, 1-3 minutes.
Transfer dough back to the bowl and allow to cool for 5 minutes. The dough should still be warm, but not hot enough to scramble the eggs.
Add in one egg at a time, mixing with an electric mixer until fully incorporated. Mix in vanilla extract, baking powder and cocoa. The final dough should be very elastic.
Spoon dough into a piping bag or plastic bag (no tip needed). Cut out bottom of piping bag 2 cm (3/4 inch) wide. Pipe out dough onto donut pan. Wet your finger tip and smooth out where the ends meet (for a more even rise). Bake for 20-25 minutes, checking in on them at minute 15 for over-browning and covering with a foil dome if need be (we didn't find it necessary!). Allow to rest in the pan for 10 minutes before removing and cooling on a rack before glazing. However, if you're doing a coating rather than a glaze, brush with melted butter and sprinkle with cinnamon 'sugar' right out of the oven.
For the glaze, sift powdered sweetener onto a bowl and whisk in the salt. Mix in the melted butter, vanilla extract and cream of choice (I love sour cream!) a tablespoon at a time until desired consistency is reached. You can thin it out even further with a little hot water and dunk the entire donuts in it. Use your fingertip here to test for thickness! Oh, and if you're glaze splits (usually the result of a cold cream), use an immersion blender to get it silky-smooth. Glaze donuts by dunking them onto the glaze (if your tops came out a bit wonky, you can always use the rounder bottoms as your new 'tops'!).
These are best enjoyed still warm and freshly glazed, but they keep quite well for a day or two stored in an airtight container in the fridge if they're glazed, or at room temp without it.
*Please see section on Sweeteners for more deets and possible substitution.**Donut pans do result in prettier (i.e. rounder) donuts. But if none is at hand, simply pipe out circles onto parchment paper. Please note that nutrition facts were estimated for the donuts with the glaze, and we found a batch to yield 9. Oh, and apologies for the awkward yield number, but every time we tried to yield 6 it simply didn't work the same.