For the minicrêpes, mix milk, flour and egg. Season with salt and allow to swell. Wash the duck breast, dab dry and scratch the skin crosswise. Heat a flat roasting pan or an ovenproof pan without fat. Sauté the duck breast only on the skin side for about 5 minutes.
Then fry on the meat side for 2-3 minutes. Season with salt and pepper. Roast duck breast in a preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for 13-18 minutes. Heat the fat in portions in a pan and fry 12 mini-crêpes in 3 portions. Remove the duck breast, wrap in aluminium foil and leave to rest. Skim the fat from the duck with a tablespoon. Reduce the mixture like a syrup. Add Hoi Sin sauce and stir in. Clean and wash spring onions and cut into wafer-thin slices. Wash the sprouts and drain well.
Reduce the mixture like a syrup. Add Hoi Sin sauce and stir in. Clean and wash spring onions and cut into wafer-thin slices. Wash the sprouts and drain well. Cut the duck breast into thin slices. Arrange crêpes, duck breast, onions and sprouts on plates. Drizzle with prepared sauce