Wash the meat, dab dry and cut into strips. Peel and chop the onions. Clean, clean and slice the mushrooms. Cut bacon into strips. Drain gherkins and cut into strips.
Heat the oil in a frying pan. Fry the meat and bacon for about 3 minutes. Add onion and mushrooms and fry for about 4 minutes, season with salt and pepper. Sprinkle with 1 tbsp. flour and sauté.
Deglaze with cream and stock. Stir in mustard. Add gherkins and let it boil down slightly for about 5 minutes. Peel, wash and grate celery in a bowl. Mix with egg and 1 tbsp. flour and season with salt and pepper.
Wash parsley, dab dry, pluck leaves from the stalks. Chop the leaves finely and fold into the celery mixture. Pour the shredded celery into 4 small or 1 large casserole dish. Spread the celery mixture over the shredded food.
Bake in a preheated oven (electric range: 175 °C/ convection oven: 150 °C/ gas: level 2) for 15-20 minutes until golden brown. Rustic baguette tastes good with it.