Place garlic, feta, 4 ounces of yogurt, lemon juice, and olive oil into food processor. Pulse a few times to combine the ingredients, then process until smooth.
If the mixture is too thick, add the remaining yogurt 1 tablespoon at a time, until the whipped feta is the consistency of hummus. The consistency will depend on the yogurt. If you prefer a little thinner, add more olive oil.
Transfer Whipped Feta to bowl, taste, and season with additional lemon juice and salt if necessary.
If serving Whipped Feta as a dip, transfer to serving bowl, drizzle with olive oil, and sprinkle optional garnish ingredients in center.
Whipped Feta will keep in refrigerator in tightly sealed container for five days.