Combine tomato paste, olive oil, garlic, parmesan cheese and half of the parsley in a bowl. Add the chicken and toss to fully coat. Refrigerate for 30 minutes.
Preheat grill to low medium heat.
Alternate the chicken and bread onto the wooden skewers. Season with salt and pepper.
Grill, turning occasionally until chicken is cooked through to an internal temperature of 160 degrees using a thermometer and the bread is slightly charred, about 10 minutes. Garnish with remaining parsley. Season with salt to taste before serving.