Heat the oven to 425°F. Toss eggplant with 2 tablespoons oil and 1/2 teaspoon salt on a rimmed sheet pan and roast for 25 to 30 minutes, turning once, until tender and browned.
Cook ziti in boiling water for 2 minutes less than the package directs, then drain. Heat remaining oil in a saucepan, stir garlic for 30 seconds, add tomatoes, tomato sauce, basil, remaining salt and pepper and simmer for 10 minutes.
Transfer pasta, eggplant and sauce to shallow containers and refrigerate within 2 hours. Chill fully before assembly.
Fold ziti and eggplant with sauce, ricotta and half the mozzarella. Divide between two 8-inch-square metal pans and top with remaining mozzarella and Parmesan.
Freeze before the final bake: cover pans tightly with foil and a second protective wrap, label and freeze for up to 2 months.
Thaw a pan in the refrigerator for 24 hours. Remove outer wrap and bake covered at 375°F for 30 minutes, then uncover for 15 to 20 minutes until the center reaches 165°F.
Rest for 10 minutes and serve 4 portions per pan. Reheat cooked refrigerated portions covered at 350°F for 20 to 25 minutes until 165°F.