If you're using dried chickpeas, start by soaking them overnight and then pressure cook or boil, reserving some cooking liquid (aquafaba).
Add chickpeas and tahini to a high-powered blender or food processor
Grind garlic in a mortar and pestle, or finely mince. Add to blender.
Add olive oil, lemon juice, salt, and desired spices.
Blend on high for 30-60 seconds, or until a thick paste is formed.
Add Greek Yogurt, and pulse. If you're not using yogurt, add a small amount of aquafaba (liquid from the can or cooking liquid) until desired consistency is reached.
Serve warm, drizzled with extra olive oil, salt, and spices. Or keep refrigerated for up to 5 days.