Begin by cutting your boneless, skinless chicken breasts into evenly sized cubes, about 1 to 1.5 inches.

In a separate bowl, whisk together ¼ cup of olive oil, ¼ cup of fresh lemon juice, and 3 minced garlic cloves. Add 1 teaspoon of dried oregano, 1 teaspoon of ground cumin, and season generously with salt and black pepper. Whisk until well-blended.

Pour the marinade over the cut chicken cubes and mix thoroughly until each piece is well-coated. Cover the bowl and refrigerate for at least 30 minutes.

If using wooden skewers, soak them in water for 20 minutes. Thread the marinated chicken onto the skewers, leaving a little space between each piece. Optionally, add sliced bell peppers or zucchini.

Preheat your grill to medium-high heat, ideally around 400°F (200°C). Once hot, cook the skewers for 10 to 12 minutes, turning occasionally.

After grilling, remove the skewers from the grill and let them rest for a few minutes. Garnish as desired and serve.