Use your blue or purple basil to make gorgeous garnet-coloured basil-infused vinegar to use or to give. Experiment with other pungent herbs like rosemary and thyme, but keep in mind that milder herbs like lemon balm and sage will produce marginal results.
Use two large handfuls of basil leaves and flowers (flowers are best for adding colour) to every litre of vinegar.
Tip: Try reducing the steeped vinegar by half, by gently boiling in a non-reactive saucepan, then using the light syrup as an old-fashioned 'shrub' by adding a teaspoon or so to soda water.
Place basil in heatproof non-reactive bowl and bruise gently with a wooden spoon. Heat cider but do not boil, pour over basil and stir gently. Cover and leave to infuse for up to two weeks.
Pour through several layers of cheese cloth (6-8) or a coffee filter, into beautiful glass jars or bottles. Discard leaves (rinse well before composting as acidic vinegar will harm plants).
Store vinegar in a cool, dark place until ready to use or give to someone you really like.