Whisk together the vinegar, garlic, lemon juice, Dijon, oregano, salt, and pepper. Using a microplane, finely grate the clove of garlic over vinegar mixture, whisk into mixture. Slowly whisk in olive oil until combined. Whisk or shake before serving.
For Greek Salad:
Toss together lettuce with cucumbers, tomatoes, shallot, olives, and feta with ¼ cup dressing.
Serve with croutons, pepperoncini peppers and additional Greek Dressing to the side.
Storage: You can prepare the salad up to 24 hours in advance. Just wait to add the croutons and dressing until ready to serve.Leftover Dressing: Store the leftover dressing for up to 2 weeks in the fridge and use it for salads or to marinate meat or veggies. Shallot Substitution: Feel free to use red onions in place of shallots--just soak red onion slices in cold water for 15 minutes to remove some of their sharpness.