Oil-free Roasting: Roast the peppers on the top rack of your oven, right under your broiler, for about 10-15 minutes. When the peppers are well-charged, remove them from the oven. Transfer peppers to an airtight container and cover. Let steam for 5-10 minutes.
Tip: If you are making the sauce alongside pasta save some of that pasta water. It's liquid gold! When in need of more sauciness add a splash of that pasta water, 1-2 tablespoon at a time.
Storage: Store the sauce in an airtight container after blending. Keep in the fridge for up to four to five days.
Freeze: Store in a freezer-safe air-tight container or bag after blending, and label with the date of freezing. It keeps fresh for up to 3 months. Defrost in the fridge overnight and reheat the next day.