Slice the tomatoes in half lengthwise. Drizzle the cut sides with olive oil and sprinkle with salt and pepper.

Heat a grill or grill pan over medium-high heat. Brush with olive oil and place the tomatoes on the grill, cut side down. Grill for 4 to 6 minutes, or until grill marks form. Flip and grill for another 3 to 4 minutes, or until tender but not collapsing.

Transfer the tomatoes to a serving platter. Season with salt and pepper and drizzle with Italian dressing. If desired, top with grated Parmesan cheese. Garnish with fresh basil and serve.