In a jar, combine 5 tbsp. of the EVOO with the lemon zest and juice, vinegar, sugar and garlic. Screw on the lid; shake to blend. Season the vinaigrette with salt and pepper. In a large bowl, combine the tomatoes, cucumbers, radishes, bell pepper, onion and cilantro. Toss with the vinaigrette; season. Transfer to a platter; create a well in the center of the salad.
In a small bowl, combine the allspice, cardamom, cumin and 1/4 teaspoon salt; spread the spices on a large plate. Roll the chickpeas in the spices to coat. In a large skillet, heat the remaining 1 tbsp. EVOO over medium. Add the chickpeas; fry until warmed through, shaking the pan occasionally, 2 to 3 minutes.
Spoon the chickpeas into the center of the salad. Dollop with yogurt, if using.