Fry both in a pan, season with salt, pepper and season with thyme. Fry the mushrooms until they no longer give off any liquid
Cut the chicken breasts apart using a butterfly cut and unfold. Fill with sliced cheese and the mushrooms.
Close and wrap tightly with bacon. That actually holds up quite well, if necessary stick a couple of toothpicks into it.
Fry them briefly in a pan and then put them in the oven at approx. 200 ° C for 30 minutes with the fresh sprigs of thyme. If necessary, cover with kitchen paper after 15 minutes and continue frying on a slightly lower heat