Start by salting your eggplant slices generously on both sides and let them sit on paper towels for 30 minutes. This draws out excess moisture and any bitterness.

While waiting, prepare the tomato topping. Mix diced tomatoes, torn basil, minced garlic, 2 tablespoons olive oil, and balsamic vinegar in a bowl. Season with salt and pepper, then set aside to let the flavors meld.

Pat the eggplant slices dry with paper towels and brush both sides with remaining olive oil.

Preheat your grill to medium-high heat (around 400°F).

Grill the eggplant slices for 4-5 minutes per side, until they develop nice grill marks and become tender.

Arrange the grilled eggplant on a serving platter and top with the tomato-basil mixture.

If using, sprinkle with Parmesan cheese while the eggplant is still warm.