In a food processor, combine the chickpeas, tahini, lemon juice, olive oil, garlic, cumin, salt, and pepper. Blend until smooth, adding a little water if necessary to reach your desired consistency.
Transfer the hummus to a serving dish and spread it out evenly.
In a small bowl, mix the Greek yogurt with a pinch of salt and spread it over the hummus.
Top the hummus with diced cucumber, diced tomatoes, chopped olives, and crumbled feta cheese.
Sprinkle the chopped parsley over the top for garnish.
Serve with pita chips or fresh veggies for dipping.