In a small bowl, combine the olive oil, Italian seasoning, and sliced garlic (if using). Add the mozzarella balls, ensuring they are fully coated in the marinade. Cover and refrigerate for at least 30 minutes to allow the flavors to meld, or leave them to marinate for up to 24 hours for deeper infusion.

While the mozzarella marinates, wash the cherry tomatoes and basil leaves, then gently pat them dry. If the basil leaves are large, tear them in half to create smaller, more manageable pieces.

To assemble the skewers, start by threading one cherry tomato onto each skewer. Follow with a fresh basil leaf, a marinated mozzarella ball, another basil leaf, and finish with another cherry tomato. Repeat until all the skewers are assembled.

Before serving, remove and discard the garlic slices from the marinade (or save them for cooking). Drizzle the assembled skewers with a tablespoon of the reserved marinade and a generous drizzle of balsamic glaze, if desired. Season with a sprinkle of salt and freshly ground black pepper to taste.

Serve immediately for the freshest flavor, or chill briefly before serving to enhance the marinated elements.