Wash and peel the white asparagus and cut off the woody ends. Cook the asparagus in boiling salted water with 1 teaspoon of sugar for about 12 minutes. Wash the green asparagus, cut off the woody ends. Cook the asparagus in boiling salted water with 1 tsp. sugar for about 6 minutes. Lift the asparagus carefully out of the water and drain well. Leave to cool down
Halve the walnut kernels lengthwise. Peel and finely dice onions. Heat 3 tablespoons of olive oil in a pan, fry the walnut halves lightly in it, add the onions and fry with them. Season with salt and pepper. Add 1 tbsp. sugar, mix in, let it caramelize slightly, deglaze with dark vinegar. Bring to the boil and simmer at low heat for about 8 minutes
Clean and wash the salad and drain well in a sieve. Mix vinegar, salt, pepper and 1 pinch of sugar. Fold in 2 tablespoons of olive oil. Mix asparagus, salad and vinaigrette. Crumble cream cheese over it and sprinkle with walnut and onion vinaigrette. Garnish with chervil