Add the herbs to the jar. Make sure the herbs are chopped up well. You want as much surface area as possible to come in contact with the vinegar.
OPTIONAL: Gently heat the vinegar in a small pot on the stove until it’s just beginning to steam. You don’t want to bring it to a boil, so keep an eye on it.
Carefully pour the vinegar over the herbs. Stir the herbs with a spoon or wood chopstick to release any air bubbles. Top with more vinegar to fill the jar, if needed.
Tightly secure a plastic lid or place the piece of parchment paper on top of the jar before securing a metal lid. Vinegar will corrode metal if it comes in contact with it.
Place the jar somewhere that you’ll see it so that you don’t forget about it. Someplace warm is ideal. Gently shake the jar every day for the first week to help keep the herbs distributed in the vinegar.
If you warmed the vinegar before infusing, you can strain out the herbs after the first week. Otherwise, let the herb vinegar infuse for another 3 weeks. You’ll want the herbs to infuse for at least 4 weeks total but you can let them infuse for up to 6 weeks, if you want.
After the 4-6 weeks, strain out the herbs using a fine mesh strainer lined with cheesecloth or an unbleached coffee filter. Squeeze out the herbs to extract all the goodness out of them.
Compost the herbs, if possible.
Label and store your herb-infused in the pantry for up to 1 year. Use liberally in cooking. Your salad dressings will never be the same.