Preheat oven to 400°. Line large rimmed baking pan with foil. Spray with nonstick spray and set aside.

Cut sweet potatoes in half lengthwise. Place, cut sides up, in prepared baking pan. Drizzle with 2 tablespoons olive oil; season with ½ teaspoon each salt and black pepper. Bake 50 to 55 minutes or until fork-tender, turning halfway through.

Place feta, Greek yogurt, and lemon zest in a food processor. Cover and pulse until smooth. With processor running, slowly pour in remaining 2 tablespoons olive oil; process 1 to 2 more minutes or until smooth. Set aside.

Combine garbanzo beans, tomatoes, shallot, green olives, Kalamata olives, 1 tablespoon each green and Kalamata olive brines, undrained capers, mint, 2 tablespoons parsley, lemon juice, garlic, and remaining ½ teaspoon each salt and pepper in a medium bowl.

To serve, top each sweet potato half with ¼ cup whipped feta and ¾ cup garbanzo bean mixture. Garnish with additional feta and parsley, if desired.