Cut the avocados in half, remove the pit, and scoop out the flesh into a blender.
Peel and chop the cucumber, and add it to the blender.
Add the garlic clove, Greek yogurt, cilantro, lime juice, salt, black pepper, cayenne pepper, and vegetable broth to the blender.
Blend until smooth and creamy.
Taste and adjust seasoning as needed.
Serve chilled and garnish with extra cilantro and a squeeze of lime, if desired.