In a blender, combine garlic, herbs, salt and sugar. Whirl until garlic is finely chopped. Add oil and vinegar and whirl again. It will emulsify - adjust to taste. If too vinegary, add a little more oil. Add lemon juice and pepper and spin again. Keeps well in refrigerator. May separate. Just shake well to use.
NOTE: To make a bleu cheese dressing, use cider vinegar instead and crumble bleu cheese in and spin VERY briefly so as not to break up the cheese too much.