Roast and Peel Peppers: Roast poblano peppers over a flame or under a broiler until charred. Steam, peel, and remove seeds.
Stuff Peppers: Fill each pepper with cheese strips.
Make Batter: Beat egg whites until stiff, then fold in yolks and salt.
Fry Peppers: Coat peppers in flour, dip in batter, and fry until golden.
Prepare Sauce: Sauté garlic and onions, add tomatoes and cumin, and simmer.
Serve: Plate peppers, top with sauce, and garnish with cilantro.