Preheat the oven to 425 (220 C) degrees.
Put the eggplant, peppers, tomatoes and onion on a large (18"x13") rimmed sheet pan. Drizzle the oil over and season with the chili pepper and salt to taste (I usually use 1-2 teaspoons Diamond kosher).
Bake 25-30 minutes, stirring halfway through, until the vegetables are softened and lightly browned on the edges.
Add the pesto, vinegar and chickpeas to the hot vegetables and stir around with a spatula. Sprinkle the greens over and stir again until the leaves wilt slightly.
Serve warm or at room temperature.
