1
Add the walnuts, coconut flour, psyllium husk powder, baking powder, and salt to a food processor, and mix until the walnuts are ground, and everything looks like flour.
2
Add the eggs and apple cider vinegar and pulse a few times until the eggs get incorporated into the dry ingredients. With the food processor running on low, gradually add the hot water. You should get a ball of homogenous, stiff dough.
3
Take the dough out, shape it into a ball, then portion it into 6 or 8 pieces (6 for bigger rolls, like for hamburgers, and 8 for smaller rolls, for sliders).
4
Shape into balls. If you want to top the rolls, dip the top in warm water, then dip them again into the sesame seeds.
5
Arrange on a baking sheet on parchment paper. In a preheated oven at 350F/180C, bake for 45 minutes, without peaking in, then turn off the heat and let them in the oven for another 30 minutes.