Balsamic Stuffed Mushrooms

Ingredients

• 30 large white button mushrooms (about 1-1/4 pounds)
• 1/2 cup chopped pancetta
• 1 medium onion, finely chopped
• 2 cloves garlic, finely chopped
• 2 cups lightly packed baby spinach leaves, finely chopped
• 1 jar (24 ounces) Bertolli^® Traditional Marinara with Italian Herbs & Fresh Garlic Sauce
• 1/4 cup plus 2 tablespoons grated Parmesan cheese, divided
• 1/2 cup plus 2 tablespoons seasoned panko bread crumbs, divided