Peel and finely chop the onion. Clean, wash and halve the mushrooms. Cut 1 slice of bacon into strips. Knead minced meat with half of the onion. Season with salt and pepper. Form a minced steak.
Heat the oil in a pan and fry the steak for about 5 minutes on each side. Remove and keep warm. Fry 1 slice of bacon crisply in frying fat, drain on kitchen roll. Fry the bacon strips and mushrooms in the cooking fat.
Add 100 ml milk and 100 ml water. Bring to the boil, stir in broth. Stir in the sauce thickener and simmer for about 2 minutes. Boil 175 ml water with 1 pinch of salt. Remove from heat and add 75 ml milk.
Stir in the puree flakes with a wooden spoon. Wash the chives, dab dry, put something aside for garnishing. Cut the rest into small rolls. Stir in the chives, except for 1 teaspoon. Season to taste.
Arrange the minced steak with sauce, puree and a slice of bacon on a plate. Garnish and sprinkle with chives.