Preheat oven to 400 degrees. Line a large, rimmed baking sheet with parchment paper and mist with nonfat cooking spray.

Place bell peppers and eggplant on baking sheet, and roast, turning once or twice, for about 40 minutes, or until eggplant is very soft and bell peppers are charred. Transfer to a large metal bowl or a brown paper bag, cover tightly with plastic wrap, and let rest/steam until cool enough to handle.

Peel skin from eggplant and bell peppers, and remove seeds from bell peppers. Place all vegetable flesh in a food processor. Add in remaining ingredients, and pulse until well combined.

Transfer mixture to a large sauce pan, season as desired with salt and pepper, and simmer over medium heat for about 15-20 minutes, allowing the dip to reduce down to about 2 cups.

Allow dip to cool, then transfer to a bowl, cover and refrigerate for at least 1 day before serving.