Almost all culinary herbs can be used to make a herb flavoured vinegar. The method could not be simpler: take a bottle of white wine vinegar and pour a little into a cup. Add your chosen herb to the bottle, for instance a long sprig of tarragon or a handful of leaves of basil. Pour back the reserved vinegar and seal the bottle tightly. Place the bottle in a warm room and leave for 1-2 weeks or until the vinegar has absorbed the aromatic oil from the herb. Use the herb vinegar as required, but store in a cool, dark place to preserve its flavour.