Before making the dough, be sure to feed your sourdough starter at least twice, allowing it to reach peak activity level.
Combine all dry ingredients (flours, salt and psyllium husk) in a mixing bowl.
Add wet ingredients (starter, water, and optional honey). Mix with a utensil first, and then you may want to use clean hands to thoroughly mix further. Or, use a stand mixer.
Form the dough into a fairly smooth ball, and set it in the bottom of a bowl. No need to knead the dough, or perform "stretch and folds" as you would with gluten-based sourdough.
Cover the bowl with a damp cloth. Set it aside in a location that is as close to 75F as possible to "bulk ferment" for 3-5 hours.
After an average of 4 hours of bulk fermentation at room temperature, gently transfer the dough into a flour-dusted (and potentially cloth-lined) banneton proofing basket of choice.
Cover the banneton with a damp lint-free towel. You can leave it at room temperature for another hour (optional) and then move it to the refrigerator, or just refrigerate immediately after transfer.
Move the banneton to the refrigerator to cold-proof the dough overnight (7 to 12 hours). Leave the dough in the fridge until immediately before transferring to hot pre-heated baking pan.
Preheat the oven to 475 degrees F. If you’re using a dutch oven or combo cooker, place it in the oven to preheat for one hour.
After an hour of preheating the baking pan, use the cutting board trick (see Note 2 below) to carefully transfer the cold dough out of the banneton and into the hot combo cooker or dutch oven. Score the top of the loaf with a bread lame while it it is still on the cutting board if desired.
Bake the loaf covered for 60 minutes, and then remove the lid and bake for an additional 5 minutes uncovered. (See Note 3 below)
Once done, immediately remove the finished sourdough loaf from the oven and combo cooker and place the loaf on a wire rack to cool.
Let the sourdough bread loaf sit at room temperature for several hours before cutting. The steam trapped inside is important moisture to retain!
Store the finished gluten-free sourdough bread wrapped in a dry lint-free cloth towel, and then inside a brown paper bag. Toasting or lightly broiling the bread helps revive stale bread that is a few days old. Freeze some while still fresh (the first day) if you do not think you'll be able to finish the loaf within 3-4 days.