Drain the quark in a fine sieve over a bowl for 4 hours.
Cover the eggs with water in a small saucepan and bring to a boil. Boil for exactly 9 minutes and quench under cold water.
Peel and halve the eggs. Remove the egg yolks with a teaspoon and place in a bowl. (Use egg whites otherwise, e.g. chop and sprinkle over a salad.)
Add 1–2 tablespoons of water to the egg yolk and mash with a wooden spoon to a creamy mass. Mix with the cayenne pepper until smooth.
Gradually stir in the drained quark. Season with salt.
Squeeze the lemon and measure out 1–2 teaspoons of juice. Mix with the vinegar into the quark mixture and refrigerate the light mayonnaise for 2–3 hours.