Pasta Salad With Eggplant, Tomatoes, And Basil

1A. FOR A CHARCOAL GRILL: Open bottom vent completely. Light large chimney starter filled with charcoal briquettes (6 quarts). When top coals are partially covered with ash, pour evenly over grill. Set cooking grate in place, cover, and open lid vent completely. Heat grill until hot, about 5 minutes.
1B. FOR A GAS GRILL: Turn all burners to high, cover, and heat grill until hot, about 15 minutes. Leave all burners on high. (Adjust burners as needed to maintain grill temperature around 350 degrees.)
2. Clean and oil cooking grate. Lightly brush eggplant with oil and sprinkle with salt and pepper to taste. Grill, turning once, until marked with dark stripes, about 10 minutes. Let cool and cut into bite-size pieces.
3. Meanwhile, bring 4 quarts water to boil in large pot over high heat. Whisk lemon juice and zest, garlic, 3⁄4 teaspoon salt, and pepper flakes in large bowl; whisk in 1⁄2 cup oil in slow, steady stream until smooth.
4. Add pasta and 1 tablespoon salt to boiling water. Cook until pasta is al dente and drain. Whisk dressing again to blend; add hot pasta, cooled eggplant, tomatoes, and basil; toss to mix thoroughly. Let cool to room temperature, adjust seasonings, and serve. (Pasta salad can be refrigerated for up to 1 day; return to room temperature before serving.)