Poblano and serrano chiles give a mild kick to this cheesy Mexican pasta.
- 3/4 lb fresh poblano chiles (about 4)
- 1/2 large white onion, cut lengthwise into 1/4-inch-wide strips (1 3/4 cups)
- 1/2 teaspoon salt
- 2 tablespoons unsalted butter
- 1 fresh serrano chile, minced, including seeds
- 2 large garlic cloves, minced
- 1/2 teaspoon dried oregano (preferably Mexican), crumbled
- 6 oz dried cavatappi or penne
- 2/3 cup crema or crème fraîche
- 4 oz queso fresco or mild feta, crumbled (1 cup)
Broil poblanos on a broiler pan about 2 inches from heat, turning occasionally with tongs, 8 to 10 minutes. Transfer poblanos immediately to a large bowl and cover. Let steam 10 minutes, then peel or rub off skins and discard stems, seeds, and ribs. Cut poblanos into 1/4-inch-thick strips.
Cook onion with salt in butter in a 12-inch heavy skillet over moderately low heat, stirring occasionally, until onion is golden, 10 to 12 minutes. Add poblanos, serrano, garlic, and oregano and cook, stirring, until fragrant, about 1 minute. Remove from heat.
While onion is browning, cook pasta in a large pot of boiling salted water until tender, 14 to 15 minutes. Reserve 1/4 cup pasta-cooking water, then drain pasta in a colander. Add pasta to chile mixture along with crema and reserved cooking water. Increase heat to high and cook, tossing, until pasta is well coated, about 1 minute. Stir in cheese.