It's funny that when I first started low carb, I'd look for substitute recipes that seem to fill the gap where I would miss the real carb food like bread. I used to love bread, but I also had a hard time finding a recipe that checked all the boxes including low carb, enabling continued weight loss/ maintenance, no negative reactions, etc. That was harder than I thought. Breads with almond or coconut flour didn't check all the boxes and caused a tickling sensation in my throat. No go. So, after better understanding my carb addiction and how even a photo of a rustic loaf of bread would seem to trigger a desire to slather it with butter and gorge, I gave up the idea. At about the same time and as I was producing ketones and burning fat, my former cravings from my carb addiction ceased. I really wasn't interested any longer in finding substitutes. The cravings for bread were no longer there. Now, that's not answering your question, but this is what happened. I don't need substitutes.

However, a family member in the past year made a bread recipe with Isopure, Whey Protein Isolate product. It is good and checked all the boxes. It's filling and satisfying. It doesn't cause cravings, it's a nice, occasional food for me with an increased amount of protein to boot. I'll try and find the recipes we used. We even made pizza crust that was very good and very filling.