Pack a glass jar as full as you can with either one or a combination of citrus peels.
Pour vinegar over the peels and herbs, if using, until the jar is full.
Use a chopstick to poke around between the peels, removing any trapped air bubbles.
Top off the vinegar in the jar as needed, until it is again full.
Cover with a lid, and place in a dark, cool area for a minimum of two weeks and up to 3 months.
Wait until the color turns golden, and the mixture smells more strongly of citrus than vinegar.
Using either a fine-mesh sieve or a coffee filter, strain the mixture. Compost the solids, and store the remaining vinegar in a glass bottle fitted with a spray nozzle.
