Boil the eggs until they are waxy or hard. Finely dice the bacon and onion. Steam the bacon until translucent. Add onions and roast until light yellow. Dust with flour, stir with milk and cook gently for about 10 minutes. Peel the eggs and cut the chives into fine rolls. Mix the sauce with the mustard and season with salt and sugar. Reheat eggs in it, do not boil. Sprinkle with chives.