Set an oven rack on the center shelf and preheat the oven to 500 degrees F. Line a large sheet pan with foil and place the red peppers on top, leaving some room between each one.
Roast for 30 to 45 minutes, turning every 15 minutes, until the skins are charred and wrinkled on all sides.
Remove the pan from the oven and quickly but carefully transfer the peppers to a resealable plastic bag, closing it to lock in the steam. Alternately, you can cover the sheet pan tightly with another layer of foil. Set aside for 25-30 minutes, or until the peppers are cool enough to handle.
Peel away the skins, then remove the stem and seeds (discard everything but the red pepper flesh and any oils the produce). Use immediately, or store in an airtight jar along with extra virgin olive oil. Roasted red peppers will keep in the refrigerator for up to 2 weeks. If properly sealed and canned, these will keep for up to one year.
This method will work with all bell peppers (red, orange, green, yellow, etc).
See my post details for notes about how to roast on the grill, gas stovetop, or under the broiler.