Eggs in Frankfurter Green Sauce

Ingredients:
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5 hard-boiled eggs
1/2 cup grapeseed oil
5 oz plain yogurt
5 oz sour cream
2 tablespoons finely chopped herbs (e.g. watercress, chives, sorrel, parsley, chervil etc)
1 garlic clove
juice of half a lemon
1 tablespoon German prepared mustard
salt and pepper to taste
1 pinch sugar
1 pickled German gherkin
1 onion

Cooking:
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1. Peel the hard-boiled eggs, cut in half, remove the yolk and mash it with the oil. Add the yogurt and sour cream.
2. Finely chop the fresh herbs.
3. Peel and crush the garlic clove and mix together with the herbs, lemon juice, mustard, salt, pepper and sugar.
4. Finely chop the egg yolk and gherkin.
5. Peel and grate the onion and mix the remaining ingredients together.
6. Serve with hard-boiled eggs.