Seeds: Add the sunflower seeds, sesame seeds, ground flax seeds, chia seeds, psyllium husks, and salt to a large mixing bowl. Give it a good mix.
Combine: Form a well at the center of the seeds and pour in the tahini and the boiling water. Stir with a spatula until well combined. Note that the psyllium forms a gel very quickly.
Transfer the mixture to a loaf pan lined with parchment paper. Use a spatula to press it down tightly into the pan.
Bake for 50 minutes at 400°F (200°C), fan. Let cool completely before slicing.
Notes
Psyllium: If you opt for psyllium husk powder, be sure to measure it accurately with a digital scale.
Storage: Put the bread in a large zip bag (I use these large reusable vacuum zip bags) or wrap the bread in plastic wrap. Then, store it in the refrigerator for 5-6 days. Refrigeration prevents oxidation and keeps the bread fresh and moist for longer.
To serve: Eat it as is or give it a quick toast to warm it up and add a light crunch.
Freeze: This bread freezes incredibly well for up to 3 months. Slice the bread completely and store the slices in a zip bag or in bundles of 2 or 3 sliced in plastic wrap.