Chiles rellenos (Spanish for “stuffed peppers”) are a traditional Mexican dish made with large, mild chile peppers—often poblano peppers—that are:Roasted and peeledStuffed, commonly with cheese, seasoned meat, or beansOften coated in a fluffy egg batter and friedServed with a tomato-based sauceThe singular is chile relleno; the plural is chiles rellenos. They’re usually savory and mildly spicy, though the heat varies by pepper.
Roast the peppers: Place the poblanos under the broiler or directly over a gas flame. Turn frequently until the skins are blackened and blistered on all sides, about 8–10 minutes.
Steam and peel: Put the hot peppers in a covered bowl or sealed paper bag for 10 minutes. Carefully peel off the loosened skins. Cut a lengthwise slit in each pepper and gently remove the seeds, keeping the peppers intact.
Stuff the peppers: Place one piece of cheese inside each poblano. Close the slit and secure with toothpicks if necessary.
Make the sauce: Blend the tomatoes, onion, garlic, broth, cumin, oregano, and salt until smooth. Heat 1 tablespoon oil in a saucepan over medium heat. Add the tomato mixture carefully and simmer for 15–20 minutes, stirring occasionally.
Heat the frying oil: Pour about 1 inch of vegetable oil into a deep skillet. Heat to 350°F over medium-high heat.
Prepare the egg batter: Beat the egg whites and 1/2 teaspoon salt with an electric mixer until stiff peaks form. In a separate bowl, lightly beat the yolks. Gently fold the yolks into the beaten whites.
Coat the peppers: Spread the flour on a plate. Lightly coat each stuffed pepper with flour, shaking off the excess. Dip into the egg batter until completely covered.
Fry: Carefully place 1–2 peppers at a time in the hot oil. Fry for about 2–3 minutes per side, until golden brown. Drain on paper towels and remove any toothpicks.
Serve: Spoon warm tomato sauce onto four plates and place one chile relleno on each. Serve immediately with rice, refried beans, or warm tortillas.