If using bamboo skewers, place them in a shallow dish of water to soak for at least 30 minutes. Cut the chicken breasts into uniform 1-inch cubes. This helps them cook evenly.

In a large bowl, whisk together the olive oil, fresh lemon juice and zest, minced garlic, Kosher salt, and freshly ground black pepper.

Add the cubed chicken to the bowl with the marinade. Toss well to ensure all the chicken is coated. Cover the bowl and refrigerate for at least 30 minutes, or up to 2 hours for best flavor. Do not marinate longer than 4 hours as the lemon juice can start to "cook" the chicken.

Preheat your grill to medium-high heat (about 400°F / 200°C) or your broiler to high. Remove the chicken from the marinade and thread the chicken pieces onto the prepared skewers, leaving a small space between each piece to allow for even cooking. Discard any remaining marinade.

Place the skewers on the hot grill grates or on a broiler pan. Grill for 10-14 minutes, turning every 3-4 minutes, until the chicken is cooked through and has nice char marks. If broiling, cook for 8-12 minutes, flipping halfway through, until golden brown and cooked.

Remove the skewers from the heat and let them rest for 5 minutes. Garnish with chopped fresh parsley, if desired, and serve hot.