Prep time: 15 minutes. Marinating time: 30 minutes to 2 hours. Grill time: approximately 12 to 15 minutes. Rest time: 3 to 5 minutes. Total time: approximately 1 hour to 2 hours 35 minutes, including marinating and resting. Servings: 4. Yield: approximately 8 skewers. Chicken ingredients: 2 pounds boneless skinless chicken breasts cut into approximately 1 1/4-inch cubes, 2 tablespoons olive oil, 3 minced garlic cloves, 2 tablespoons fresh lemon juice, 1 teaspoon lemon zest, 1 teaspoon dried oregano, 1 teaspoon paprika, 1/2 teaspoon ground cumin, 1/2 teaspoon onion powder, 1/2 teaspoon salt, 1/4 teaspoon black pepper, and 1 tablespoon chopped fresh parsley. Vegetable ingredients: 1 red bell pepper, 1 green bell pepper, 1 red onion, optional 1 zucchini, 1 tablespoon olive oil, 1/2 teaspoon dried oregano, 1/4 teaspoon salt, and 1/4 teaspoon black pepper. Sauce ingredients: 1/2 cup plain Greek yogurt, 1 tablespoon fresh lemon juice, 1 minced garlic clove, 1 tablespoon chopped parsley, 1/2 teaspoon dried dill, 1/4 teaspoon salt, and 1 to 2 tablespoons water if needed. For serving: 2 cups cooked rice or cauliflower rice, 1 small sliced cucumber, 1 cup cherry tomatoes, 1 medium lemon cut into wedges, and 1 tablespoon chopped fresh parsley. Cut chicken into even cubes. Mix chicken marinade and toss chicken until coated. Cover and refrigerate for 30 minutes to 2 hours; never marinate raw chicken at room temperature. Cut vegetables into skewer-sized chunks and season with olive oil, oregano, salt, and pepper. Thread chicken and vegetables onto metal or soaked wooden skewers. Preheat grill or grill pan over medium-high heat and lightly oil. Grill approximately 12 to 15 minutes, turning occasionally, until the thickest chicken pieces reach at least 165°F (74°C). Do not rely on grill marks alone to determine doneness. Mix Greek yogurt sauce ingredients, adding water to adjust consistency. Rest cooked kebabs for 3 to 5 minutes, then serve over cooked rice with cucumber, tomatoes, lemon wedges, parsley, and garlic yogurt sauce. For an oven variation, bake at 425°F (220°C) until chicken reaches 165°F (74°C), generally about 15 to 25 minutes depending on skewer size and thickness. Optional variations include boneless skinless chicken thighs, mushrooms, yellow peppers, crushed red pepper flakes, smoked paprika, or couscous instead of rice. These variations are not included in nutrition values. Refrigerate cooked leftovers promptly in airtight containers at 40°F (4°C) or colder for 3 to 4 days; store yogurt sauce separately and use within approximately 3 days for best quality. Reheat chicken thoroughly to 165°F (74°C). Freeze cooked chicken and vegetable kebabs without sauce for up to 2 months for best quality. Nutrition values are approximate per serving based on 4 servings using chicken breast, optional zucchini, all measured oil, yogurt sauce, and 2 cups total cooked white rice. Actual values depend on chicken size, rice variety, sauce quantity, and portion size.