I like to make this recipe in the summertime when we have access to the peak-season peppers: Corno di Toro, Lipstick, and Jimmy Nardello. I like to char them on the grill, for some smoky flavor. This also allows the tougher outer skin to come right off. If grilling’s not feasible at home, just roast the peppers in the oven at 375°F (190°C). Either way, please don’t char them over a gas range! It gives the peppers a really artificial flavor and an aroma of gas.