1. Wash the mushrooms with lemon water, then cut them into slices.
2. Melt the butter and as soon as it foams, sear the escalopes on both sides without letting them brown.
3. Remove them from the pan and keep them warm.
4. Pour the white wine into the pan, bring to a boil, add the mustard. As soon as it is dissolved, put the escalopes back into this mixture over low heat.
5. Season with salt and pepper.
6. Add the mushrooms and the fresh cream.
7. Then let it cook for 10 to 15 minutes (keep an eye on it... there's nothing better!)
8. When serving, place the escalopes on a serving dish, then mix the egg yolks with a few spoonfuls of sauce and, off the heat, add this mixture to the sauce.
9. Stir and if necessary, reheat without letting it boil.
10. Pour this sauce over the escalopes.
11. Enjoy your meal!