Preheat oven to 350.Cut the peppers in half and de-seed them. Brush them with oil and place them face down on a lined baking sheet.Roast for about 40 minutes.Once the peppers are roasted, remove the skins.Place the peppers and the remaining ingredients in a saucepan on the stove.Cook on low, covered for about 20 minutes.Use an immersion blender to blend until smooth. You can also transfer to a regular blender if you wish.