How to Make It
Preheat the oven to 425° and lightly oil 2 large, rimmed nonstick baking sheets. Spread half of the eggplant cubes on each sheet in a single layer. Lightly brush the eggplant with olive oil and season with salt and pepper. Roast the eggplant for about 20 minutes, until softened and beginning to brown around the edges.
Meanwhile, in a large skillet, heat the 2 tablespoons of olive oil. Add the red pepper and cook over moderate heat until starting to soften, about 2 minutes. Add the onion and cook, stirring a few times, until softened, about 3 minutes. Add the garlic and cook until fragrant, about 1 minute. Stir in the vinegar and season with salt and pepper.
Transfer the eggplant to a large bowl. Add the red pepper mixture and the basil. Season with salt and pepper and toss gently. Serve warm or at room temperature.