Preheat Grill:
Heat your grill to medium.

Prep the Vegetables:
Slice the onion crosswise into 1½-inch rounds and secure with skewers to keep them intact. Trim the eggplants and slice into 1-inch thick rounds.

Roast the Garlic:
Wrap the whole head of garlic in foil and place on the grill. Cook for about 20 minutes, turning occasionally, until softened and golden.

Grill the Veggies:

• Place the peppers on the grill cut side down. Add onions and tomatoes. Grill, brushing occasionally with ½ cup of the olive oil and keeping the lid closed as much as possible.

• Grill for about 15 minutes, turning once, until tender and charred.

• Grill the eggplant slices until browned and tender, about 10–15 minutes total.

Steam the Peppers:
Transfer grilled peppers to a plate and cover tightly with plastic wrap to steam for 10 minutes. Peel off the charred skin once cooled.

Chop and Combine:
Dice the eggplant, tomatoes, onions, and peeled peppers into 1-inch pieces. Place in a large mixing bowl.

Make the Dressing:
Squeeze the roasted garlic cloves into a small bowl. Whisk in the balsamic vinegar, remaining ½ cup olive oil, capers, olives, salt, pepper, and fresh basil.

Assemble the Dish:
Pour the dressing over the chopped grilled vegetables and toss gently to combine. Transfer to a serving bowl or platter and sprinkle with toasted pine nuts just before serving.