It is a mystery

How does gluten-free sourdough work? I thought gluten = bread, more or less; the sponge relies on gluten for structure.

That all sounds really good. Sometimes cheese works better if it stays fully enclosed; I used to make cheese buns with some fairly dry cheese and they'd get steamed during baking and stay softer if the cheese all stayed on the inside of the bun. (which was fairly challenging without resorting to a low cheese/bun ratio.)