Cut bacon into very fine cubes and fry in a small frying pan until crisp. Finely dice the onion. Drain and finely dice mustard cucumbers. Clean scallions and cut the light green and white into 1/2 cm wide diagonal rolls.
Melt butter in a saucepan. Saute onions in it until translucent.
Dust with flour and sweat briefly. Fold in mustard and extinguish with milk and white wine. Fold in the crème fraîche and cook for 7 minutes over medium heat, stirring.
Cook the eggs in boiling water for 7 minutes, rinse and peel. Pluck tarragon leaves, chop coarsely. Add to the sauce form with the crispy bacon cubes, mustard pickles and spring onions and simmer for another 3-4 min on low heat. Season with pepper, juice of one lemon, salt and 1 pinch of sugar and bring to the table with the eggs.
Serve with mashed potatoes with chives.
Notes: instead of tarragon mustard used coarse-grained Rotisseur mustard plus freeze-dried tarragon (Goutess), also replaced the fresh with freeze-dried tarragon. Very tasty.
Our tip: Fresh chives are much more aromatic than dried!