Step 1: Prepare your ingredients. Wash cucumbers. If using regular cucumbers, peel them and scoop out any large seeds. Roughly chop the cucumbers.
Step 2: Scoop the flesh out of the ripe avocados, discarding the pits and skin.
Step 3: Combine chopped cucumber, avocado flesh, Greek yogurt, fresh lime juice, cilantro (if using), minced garlic, vegetable broth, salt, and black pepper into a high-speed blender.
Step 4: Blend on high speed until the mixture is completely smooth and creamy. If the soup is too thick for your preference, add a little more vegetable broth or water, one tablespoon at a time, until the desired consistency is reached. Scrape down the sides of the blender as needed.
Step 5: Taste the soup and adjust seasonings. You may want to add more salt, pepper, or lime juice to brighten the flavors.
Step 6: Pour the blended soup into an airtight container. Refrigerate for at least 1-2 hours, or until thoroughly chilled. The chilling process allows the flavors to meld and intensifies the refreshing quality of this summer soup.
Step 7: Serve the chilled soup in bowls. Garnish with a sprinkle of fresh chopped cilantro, a drizzle of olive oil, or thin cucumber slices, if desired. Enjoy as a light lunch, appetizer, or healthy dinner.