Mostly. The straw cost 1:50 euro a bale from a local farm, and the mud, totally free, from our occasionally sluggish and oozy river that passes through the garden. Ezra, balanced on a plank, shovelled the mud into a wheelbarrow and we added the straw bit by bit until (hopefully) the right texture was achieved. Time and weather will tell, but from looking at various Youtubes on how to do cob (torchis in French), I think we did ok.
I'd already a day nailing and screwing bits of plank, sticks, etc onto the inside to hold up the mud mixture and so far, it's looking solid. Next, the roof, and we're going to attempt to do DIY slate and zinc. Such is this structure's absurd over the top-ness that we might have to honour it with a few unusual birds as well as yr usual rusty types.