- 2 dried guajillo chiles, stemmed, seeded, thinly sliced
- 2 dried ancho chiles, stemmed, seeded, thinly sliced
- 1/2 cup (1 stick) butter
- 3 shallots, chopped
- 2 whole chipotle chiles (from can), drained, stemmed, seeded, sliced
- 1 cup water
- 2 tablespoons chopped fresh chives
- 1 3-pound beef tenderloin roast
- 6 tablespoons olive oil
- 2 teaspoons salt
- 1 teaspoon ground black pepper
- 1 tablespoon chopped fresh parsley
- Heat large skillet over medium-high heat. Add guajillo and ancho chile slices. Toast until fragrant and beginning to darken, stirring often, about 30 seconds. Add butter, shallots, and chipotle chiles. Stir just until chiles are coated with butter and shallots begin to soften, about 2 minutes. Add 1 cup water and simmer until dried chiles are soft and all water has evaporated, about 15 minutes. Mix in chives; season with salt. (Can be made 1 day ahead. Cover and chill. Rewarm before using.)
- Preheat oven to 450°F. Coat beef with 3 tablespoons oil, salt, and pepper, then parsley. Heat remaining 3 tablespoons oil in large ovenproof skillet over high heat. Add beef and sear until brown on all sides, about 6 minutes. Transfer skillet with beef to oven. Roast until meat thermometer inserted into center of roast registers 125°F for medium-rare, about 30 minutes. Let beef stand 10 minutes.
- Cut beef into 1/2-inch-thick slices. Spoon chile butter over and serve.