How to Make It
In a small saucepan, cover the chiles with water. Boil over moderately high heat until slightly softened, about 2 minutes. Cover and let soak for 1 hour.
Drain the chiles, reserving the soaking liquid, and transfer them to a food processor. Add the oil, garlic, caraway, coriander and cumin and season with salt. Puree until smooth, adding enough of the reserved chile liquid to blend the sauce. Transfer to a bowl.