20 large black olives, pitted and chopped
1/4 cup finely chopped parsley
1 teaspoon capers, chopped
1 clove garlic, finely chopped
1 hard-boiled egg yolk
1 teaspoon white vinegar
freshly ground black pepper to taste

Mix the olives, parsley, capers, and garlic in a small bowl until blended.
Add the egg yolk, vinegar, and pepper and mix until creamy