Place the peppers directly onto the burners of a gas stove. Cook the peppers, turning frequently, until they are charred on all sides. Put the peppers into a bowl, cover with plastic wrap, and let them steam for about 15 minutes. (If you do not have a gas stove preheat your oven to 400 degrees F. Coat the peppers with some olive oil and place them on a baking sheet. Cook the peppers until they are soft and have collapsed, about 1 hour. Set the peppers aside until they are cool enough to handle.)
Peel, stem, and seed the peppers; cut them into wide strips. Place the warm pepper strips into a shallow serving dish. Top with the oregano, garlic, olive oil, and vinegar. Season them with salt and pepper and mix them gently to combine the flavors. Let them sit to cool and serve at room temperature.