Directions

1. Place chiles in a small, dry, heavy-bottomed skillet over medium heat, and toast until slightly darkened, turning once, about 40 seconds. Transfer to a small heatproof bowl and pour over boiling water. Let stand until softened, about 20 minutes.
2. Using a slotted spoon, transfer chiles to the jar of a blender. Add 1 cup soaking liquid and garlic; blend until smooth. Set aside.
3. Place orange juice in a small saucepan over medium heat. Cook until liquid is reduced by half; add dulce de leche and chicken stock. Bring mixture to a simmer and immediately remove from heat; set aside.
4. Working in batches, season duck with salt and pepper and place, skin side down, in a large heavy-bottomed skillet over medium heat. As fat begins to render out, drain into a heatproof bowl and discard or save for another use. Continue cooking until skin is well-browned, about 15 minutes. Turn, and continue cooking duck until meat is browned, about 3 minutes more. Transfer duck to a plate and repeat process with remaining duck breasts.
5. Return all duck breasts to skillet, cover, and cook until an instant-read thermometer inserted horizontally in the center of a breast registers 135 degrees for medium-rare, about 6 minutes. Transfer duck to a carving board and let stand, uncovered.
6. Pour out and discard all but 2 tablespoons fat from skillet. Add reserved chile and orange juice mixtures to skillet, along with any duck juices that have accumulated on the cutting board. Place over medium-high heat and cook, stirring, scraping up any browned bits that have accumulated in the bottom of the skillet, until thickened, about 6 minutes. Whisk in butter until melted. Season with salt, and chopped cilantro.
7. Slice duck breasts and serve immediately with sauce.