Eggplant benefits from judicious use of oil and salt.
Preheat oven to 475 degrees. Cut eggplants into 1-inch cubes; divide between 2 rimmed baking sheets.
Dividing evenly, drizzle with olive oil, coarse salt, and ground pepper; toss to coat. Spread in a single layer; roast, turning once, until golden and tender, 25 to 30 minutes. Cool on sheets.