Combine lemon juice, garlic, oregano, salt, and pepper in a bowl - whisk in oil. Add chicken cubes and combine them. Cover and let marinate in the refrigerator for 2 hours.

Cut cauliflower into florets, removing as much of the stem as possible and pulse in a food processor until grated.

In a large bowl toss together the grated cauliflower, tomatoes, cucumber, onion, parsley, and mint leaves.

In a small bowl, whisk the oil, lemon juice, zest, cumin, salt, and pepper. Pour the dressing over the cauliflower mixture and toss well to combine. Cover tightly and place in the refrigerator for at least 1 hour before serving.

Remove chicken from bowl and discard marinade. Thread chicken onto 4, 10 inch skewers.

Heat grill pan over high heat. Place skewers on the grill pan and cook for 6 minutes or until done, turning often. Serve over tabbouleh.