Mix together olive oil, lemon juice, minced garlic, paprika, cumin, salt, and pepper in a bowl to create the marinade.
Add the chicken cubes to the bowl and toss thoroughly until all pieces are coated in the marinade. Cover and refrigerate for at least 1 hour, or overnight for deeper flavor.
Soak bamboo skewers in water for at least 30 minutes to prevent burning during grilling.
Thread the marinated chicken pieces onto the skewers, alternating with pieces of bell peppers, red onion, and zucchini for a colorful, balanced look.
Preheat your grill to medium-high heat until it’s hot and slightly smoky, with a gentle sizzle when you hold your hand above the grates.
Place the skewers on the grill, spacing them out evenly. Let cook for about 4-5 minutes per side, until the chicken is opaque and has nice char marks, and the vegetables are tender with caramelized edges.
Turn the skewers carefully using tongs to ensure even grilling and prevent burning. You’ll hear a satisfying sizzle and see the marinade caramelize on the surface.
Check the internal temperature of the chicken with a meat thermometer; it should read 165°F (75°C) to ensure it’s safely cooked through.
Remove the skewers from the grill and let rest for a few minutes. The cooked chicken should be juicy, with a slight char and smoky aroma, ready to serve.
Serve hot, garnished with fresh herbs if desired, and enjoy the vibrant flavors and smoky textures of these grilled chicken skewers.