Cube the meat and vegetables to similar sizes.
Assemble the marinade by combining the oil, vinegar, salt, pepper, herbs and zest; reserve some to drizzle on the meat after it comes off the grill.
Assemble the skewers, starting with the fresh mozzarella.
Grill the skewers for 5-6 minutes.
Other types of seasonal summer vegetables such as red peppers or eggplant can also be substituted. Use the extra marinade in the cup to enhance the flavor.