Cook the pasta according to the package directions. Reserve ¼ cup of the cooking water. Drain the pasta and return it to the pot.
Meanwhile, heat the oil in a large nonstick skillet over medium-high heat.
Add the eggplant. Cook, tossing occasionally, until golden brown and tender, 8 to 10 minutes.
Add the tomatoes, garlic, red pepper, ¾ teaspoon salt, and ¼ teaspoon black pepper. Cook, tossing, until the tomatoes soften, 2 to 3 minutes.
Add the tomato mixture to the pasta, along with the mozzarella and reserved cooking water. Toss to combine. Sprinkle with the mint.