1. Preheat oven to 450°F. Place a wire rack on a large baking sheet. Arrange whole bell peppers on the rack.
2. Roast peppers in the center of the oven, turning occasionally with tongs, until blackened in places, 30 to 40 minutes.
3. Transfer the peppers to a large bowl and cover with plastic wrap. Let steam for 10 minutes. Uncover and let cool.
4. With a paring knife, remove stems, skins and seeds. If serving as antipasto, combine accumulated juices with peppers.