1/2 cup vinegar (balsamic, apple cider, red wine, ...)
1/4 cup oil (olive, canola, sunflower, ...)
2 tablespoons mustard (Dijon, classic yellow, ...)
1 small bunch of a fresh herb (dill, parsley, chives, basil, oregano, ...)
2 cloves garlic, mashed
salt to taste (table salt, soy sauce, Braggs Liquid Aminos, ...)
black pepper to taste
Wash and chop the herbs. Mix everything together and shake well.
My favorite version is with balsamic vinegar, olive oil, yellow mustard, parsley, and soy sauce, but you will figure out your own favorite match of ingredients.
Keeps in my fridge for at least a week.