1. Prepare grill to medium-high heat.
2. To prepare dressing, combine first 5 ingredients in a bowl, stirring with a whisk.
3. To prepare vegetables, brush 1/4 cup dressing evenly over tomatoes, peppers, zucchini, onion, and eggplant. Place vegetables on grill rack coated with cooking spray; grill 5 minutes on each side or until lightly charred. Arrange vegetables on platter; brush with remaining dressing. Arrange prosciutto, capocollo, and cheese on platter. Sprinkle platter with basil, capers, olives, and 1/8 teaspoon salt.
Wine note: Easygoing tannins make northern Italy's Valpolicella the go-to red wine for cured meats. Without the use of oak, Tenuta Sant'Antonio Nanfré Valpolicella 2007 ($13) lets its fruit flavors shine. The cherry flavors and earthy notes meld beautifully with the charred vegetables. —Jeffery Lindenmuth