Cut the bacon into cubes and fry in a pan. Drain the fat.
Divide the mushrooms into quarters, fry in a pan in a little oil and set aside.
Cut the onion into cubes and lightly sweat in the pan in a little fat together with the sprig of thyme.
When the onions are ready, add a little white wine and chicken broth and let everything boil until most of the liquid has boiled away.
Let the onions cool and mix the chicken with mushrooms and bacon.
Mix mayonnaise and crème fraiche, season with lemon juice and add the remaining ingredients to the mixture, season with salt and pepper.
Place the chicken salad on a slice of toast and garnish with fried bacon.