Cut the chicken breast into 1-inch cubes and place them in a medium mixing bowl.
Chop the red bell pepper, red onion, and zucchini into 1-inch pieces similar in size to the chicken.
In a small bowl, whisk together the olive oil, lemon juice, dried oregano, garlic powder, sea salt, and black pepper.
Pour the marinade over the chicken and vegetables, tossing well to ensure every piece is thoroughly coated.
Thread the chicken and vegetables onto skewers, alternating between the protein and the colorful produce.
Preheat a grill or grill pan over medium-high heat and lightly grease the surface.
Grill the skewers for 10-12 minutes, turning occasionally, until the chicken is cooked through and the vegetables have a beautiful light char.