Cut the avocado into chunks and place in a food processor with the 1 cup plain Greek yogurt, 1 1/2 Tbsp fresh lime juice, 1 clove garlic, 2 Tbsp chopped fresh parsley (or 2 tsp dried), 1–2 tsp chopped fresh dill (or 1/2 tsp dried), 2 tsp chopped fresh chives (or 3/4 tsp dried), 1/2 tsp onion powder, and salt and freshly ground black pepper to taste.

Pulse the mixture until it is mostly blended, stopping once or twice to scrape down the sides of the bowl so everything combines evenly.

With the processor running, add milk 1 Tbsp at a time until the dressing reaches your desired thickness, using up to 6 Tbsp total.

(Optional) For a slightly richer dressing, substitute 2 Tbsp of the milk with 2 Tbsp olive oil; add the oil while you are adjusting consistency.

Taste and adjust seasoning; add a little more salt, pepper, or chopped herbs if desired and pulse briefly to combine.

Transfer the dressing to an airtight container and store in the refrigerator.