The tart is constructed using calf sweetbreads, a sauce made from stock and rue, and then filled with maitake and sweetbreads.
The sweetbreads are prepared a few days earlier – look for any number of instructions on the internet.
The tart is a pâte brisée dough, par baked for 15 minutes at 375, the sauce is cooked and kept warm, the carrots simmered, and the sweetbreads sautéed in butter or Olive Oil prior to assembling.
Once you have everything ready, fill the tarts and bake again for another 15 minutes at 400 degrees.
Eat, make another, eat. Repeat. It is that good.