2 medium eggplants, peeled
3 red bell peppers, seeded
1 large or 2 medium red onions, peeled
2 garlic cloves, minced
3 tbsp. good-quality olive oil
1 1/2 tsp. Kosher salt
1/2 tsp. freshly ground black pepper
1 tbsp. tomato paste
Preheat oven to 400°F. Cut eggplants, bell peppers and onions into 1-inch cubes. Toss them in a large bowl with garlic, olive oil, salt and pepper. Spread them on a baking sheet. Roast for 45 minutes, until the vegetables are lightly browned and soft, tossing once during cooking. Cool slightly.
Place the vegetables in a food processor fitted with Steel Blade; add tomato paste and pulse 3 or 4 times to blend. Taste for salt and pepper.