Chile Sauce for Enchiladas

This sauce, a Big Daddy original, is truly scrumptious.  I use it when I make my chicken enchiladas.

Heat the oil in saucepan over medium low heat. Add onion, garlic, oregano and cumin. Sauté until onion is almost tender, about 10 minutes. Mix in chili powder and flour. Mix until flour is completely incorporated. Gradually whisk in the broth, increase heat and simmer, stirring frequently, for about 35 minutes. Remove from heat. Whisk in chocolate and chipotle en adobo and salt and pepper. Allow to cool.

Notes:

1. Mexican oregano isn't related to the Mediterranean variety but is an entirely different herb.  It can be hard to find in American markets so feel free to substitute.
2. Chipotle en Adobo can usually be found in the ethnic sections of large markets, or you can make your own.