makes 1 cup

1 tablespoon Dijon mustard
4 tablespoons red wine vinegar
1 teaspoon granulated sugar
1/2 teaspoon salt
1/2 teaspoon ground black pepper
1/2 cup olive oil
2 tablespoons minced parsley and/or chopped fresh chives

In a mixing bowl, whisk mustard, vinegar, sugar, salt and pepper. Slowly whisk in oil until mixture thickens.
Adjust seasoning to taste.
Stir the herbs. Whisk again just before serving.