Preheat the oven to 175 °C/ 350 °F.
Use a kitchen scale to measure all the ingredients carefully.
I used defatted sesame seed flour but you can try sesame seed meal instead and use less water.
To make sesame seed meal, I just blend the seeds until powdered (just like I do with flax seeds to make flax meal).
I used Sukrin sesame flour (UK) but you can use this brand too (US) - both should be defatted.
Mix all the dry ingredients apart from the seeds for the topping in a bowl: sesame flour, coconut flour, flaxmeal, psyllium powder, ...
Do not use whole psyllium husks - if you cannot find psyllium husk powder, use a blender or coffee grinder and process until fine.
If you get already prepared psyllium husk powder, remember to weigh it before adding to the recipe.
I used whole psyllium husks which I grinded myself.
Do not use just measure cups - different products have different weights per cup! ..., baking soda, cream of tartar, garlic powder, ...
Cream of tartar and baking soda act as leavening agents.
This is how it works: To get 2 teaspoons of gluten-free baking powder, you need 1/2 a teaspoon of baking soda and 1 teaspoon of cream of tartar (double in this recipe of 10 buns).
If you don't have cream of tartar, instead you can use apple cider vinegar and add it to the wet ingredients.
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onion powder and salt.
Add the egg whites and eggs and process well using a mixer until the dough is thick.
The reason you shouldn't use only whole eggs is that the buns wouldn't rise with so many egg yolks in.
Don't waste them - use them for making Home-made Mayo, Easy Hollandaise Sauce or Lemon Curd.
Add boiling water and mix until well combined.
Using a spoon or hands, form the buns and place them on a non-stick baking tray or a parchment paper.
They will grow in size as they bake, so make sure to leave some space between them.
Top each of the buns with sesame seeds (or any other seeds) and press them into the dough, so they don't fall out.
Place in the oven and cook for 55-60 minutes.
Remove from the oven, let the tray cool down and place the buns on a rack to cool down to room temperature.
Store them at room temperature if you plan to use them in the next couple of days or in the freezer for future use.
Top with butter or cream cheese, burger meat and meat-free toppings.
When ready to be baked, just add the wet ingredients!