1½ tablespoons of fresh parsley finely chopped
1½ tablespoons of fresh tarragon finely chopped
1½ tablespoons of fresh sage finely chopped
1½ tablespoons of fresh chives finely chopped
1 tablespoon of capers, drained and finely chopped
3 anchovies finely chopped
1 clove garlic, finely chopped
2 teaspoons Dijon mustard
2 teaspoons Worcestershire sauce
2 teaspoons good red wine vinegar
125g softened salted butter