Puebla, Mexico — the preparation is most closely associated with Puebla and is one of the states iconic dishes. Variations exist across Mexico.
Chile rellenos (filled chiles) are one of Mexican cuisines most technically demanding preparations — a large poblano chile (Capsicum annuum var. poblano) is fire-roasted, peeled, slit, stuffed with cheese or picadillo, dipped in a light egg batter, and fried. The six-stage technique: (1) Fire-roasting: the poblano is held directly over a gas burner or charcoal grill, turning frequently, until the entire skin is blistered and charred — approximately 8–10 minutes for a full blackening. (2) Sweating: the charred chile is placed in a plastic bag or covered bowl for 15–20 minutes; the steam loosens the charred skin from the flesh. (3) Peeling: under cool running water, the charred skin is rubbed off — the chile must retain its structural integrity; torn or split chiles cannot be stuffed. (4) Seeding: a single lengthwise slit is made below the stem and the seeds and membrane are removed carefully. (5) Stuffing: Oaxacan quesillo (string cheese) or Chihuahua cheese (melting cheeses) are most common; picadillo (seasoned ground meat with raisins and almonds) is the classic Puebla filling. (6) Battering and frying: egg whites are beaten to stiff peaks, yolks folded in, the stuffed chile dipped and fried in 5cm of hot oil at 175°C.
A perfect chile relleno has layers of flavour: the smoky, slightly bitter roasted poblano skin, the sweet, mild flesh, the rich melted cheese interior, and the light egg batter exterior — all anchored by the fruity, gentle heat of the poblano.
The full blacken on the fire: partial blackening produces skin that tears on the chile flesh rather than separating cleanly Do not rinse with cold water immediately — the steam in the sweat bag loosens the skin; cold water washes away flavour The egg batter must be beaten to stiff peaks — under-beaten whites produce a dense, oily batter rather than a light, airy coating Fry temperature: 175°C; too low produces soggy batter; too high chars the batter before the interior is heated
For the most flavourful chiles rellenos, use freshly made queso Oaxaqueño or Chihuahua cheese; the melting and stretching of fresh cheese is irreplaceable The residual char on a not-fully-peeled chile adds flavour complexity — a few small charred spots left on the peeled chile are a feature, not a flaw For service at volume, stuff and refrigerate the chiles up to 4 hours before battering and frying
Under-charring — skin that has not been fully blistered will not peel cleanly, tearing the chile flesh Over-stuffing — the batter cannot seal around an overfilled chile and it splits during frying Over-beating the yolks into the whites — deflates the foam and produces a dense batter
Diana Kennedy, The Art of Mexican Cooking; Rick Bayless, Authentic Mexican; Pati Jinich, Treasures of the Mexican Table