David: The searing is key, you’re right. I had hoped to do that with the quinoa, but it’s not quite that sort of thing. I think the quality of the heat is almost as important as the ingredients; you need to cook it hot enough to sear the outside before the inside cooks. My little fire last night didn’t do that.

I think one difference between seitan and ground beef is that ground beef has an inherent crumbly quality that seitan lacks – you can cut seitan, but you can’t pull it apart or shape it very well. (This may be the one case where seitan is not the universal meat-substitute.) Tofu might be closer to the mark, maybe, if you had something to bind it together? These are things to ponder. I hope you’ll come and help me test some of these!

My second thought is that you want something that doesn’t just scorch or become dry when exposed to heat, you want it to sear and tighten and toughen, and also exude juices.

The former might be achieved through eggs or gluten (or flax?), the other makes me think there needs to be some way to trap fat or oil or broth or juice inside the burger, like vacuoles.

Olive oil? Solid-at-room-temperature fat, like butter or shortening? Grapes? Seedless pomegranates?