Clean the mushrooms and halve them according to size. Peel and halve onions and cut them into fine strips. Wash the meat and dab dry
Heat 2 tablespoons of oil in a frying pan, fry the mushrooms in it while turning, season with salt and pepper, remove. Add onions to the frying fat and fry over medium heat until golden brown, turning several times. Sprinkle with sugar and allow to caramelize. Add mushrooms
Dust with flour, sweat on and gradually deglaze with cream and stock while stirring. Bring to the boil and simmer for 3-4 minutes, season with salt and pepper
In the meantime heat 3 tablespoons of oil in a pan, fry the meat for 8-10 minutes, turning it over, then season with salt and pepper. Wash the thyme, shake dry and pluck the leaves from the stalks
Put a slice of bread on each plate. Cut the meat open. Spread on the breads, spread the sauce evenly over them and sprinkle with thyme