Preheat the oven to 450°F to 500°F
Line a baking sheet with foil or parchment
Wash and dry the peppers
Leave peppers whole or cut them in half and remove seeds and stems
Place peppers on the baking sheet skin-side up if cut, or whole if not cut
Roast for 20 to 30 minutes, turning once if needed, until skins are blistered and charred
Remove peppers from the oven
Transfer peppers to a bowl and cover tightly with plastic wrap or a lid
Let peppers steam for 10 to 15 minutes
Peel off the skins
Remove any remaining seeds and stems
Use immediately or store in an airtight container