Cut the avocado in half lengthwise, twist the two halves apart, remove the pit, and scoop out the flesh with a spoon. Discard the skin and the pit.
Peel the garlic, wash the cilantro leaves and stems (we're using both), measure out all the other ingredients: olive oil, water, yogurt, and lime juice*.
Add all the ingredients into a food processor.
Blend until thick and smooth. Adjust the consistency of the dressing by adding more water to thin it out (if necessary). Season with salt and pepper to taste.