Heat the oven to 450°F or position the rack under the broiler about 4 inches from the heat source and turn it to high. Put the peppers on a rimmed baking sheet lined with foil. Roast or broil, turning the peppers as each side browns, until they have darkened and collapsed, 15 to 20 minutes under the broiler, 50 to 60 minutes if roasting.
Gather up the corners of the foil from the pan and tightly wrap the peppers (use a kitchen towel to help if the foil is too hot). Cool until you can handle them, about 15 minutes, then remove the skin, seeds, and stems. (You can do this under running water to make it a little easier.) Don’t worry if the peppers fall apart.
Serve the peppers within an hour or so, sprinkled with a pinch of salt and drizzled with 2 tablespoons olive oil, or more if you like. (Or drizzle them with 1 or 2 tablespoons of olive oil and store them in the refrigerator for up to a few days; bring them back to room temperature before serving.)