I have never tried to make it because it is a hard sauce to make. However, I have this recipe that a friend gave to me. There might be an easier recipe but I haven't found it.
12 ounces whole dried anchos and pasilla chiles
1 to 2 chiles de árbol or dried chipotles
Water
6 tablespoons sesame seeds
1 teaspoon anise seeds
1/2 teaspoon cumin seeds
4 tablespoons peanut oil or lard
3/4 cup pecans or walnuts, chopped
6 garlic cloves, unpeeled
6 whole Italian plum tomatoes
4 cups chicken stock
1 medium onion, chopped
1 day-old corn tortilla, quartered
2 ounces unsweetened chocolate
1 1/2 ounces Ibarra® Mexican chocolate
1 teaspoon ground canela (cinnamon)
1/2 teaspoon salt
6 whole cloves
Break stems off chiles and remove seeds. Rinse chiles. Toast chiles until fragrant in a heavy skillet, turning them frequently. Transfer chiles to a large saucepan and cover with water. Simmer over medium heat for about 30 minutes until softened.
While the chiles simmer, toast sesame seeds over medium heat in the skillet. Don't let them burn. Spoon the seeds into a blender.
Toast the anise and cumin seeds in the skillet until fragrant and add them to the blender.
Pour 1 tablespoon of the oil into the warm skillet and stir in the nuts. Sauté until lightly colored and fragrant. Add the nuts to the blender.
Wipe out the skillet and increase heat to medium-high. Scatter the garlic cloves in the skillet, turning the cloves occasionally so that they soften and darken on all sides. Remove and set aside until cool enough to handle.
Add tomatoes to the skillet, turning occasionally as they soften and darken. The skins will split a bit during the process. Remove the tomatoes and set them aside until cool enough to handle. Remove the skins from the garlic and tomatoes and add both to the blender.
Pour 1 cup of the stock into the blender. Purée the mixture for 2 minutes. The sauce will become smooth but a little grainy. Pour the sauce into a large bowl.
Drain chiles lightly from their cooking liquid, reserving 1 cup of the liquid. Place the chiles and about 1/2 cup of the reserved liquid in the blender and purée. Pour the chiles into the bowl with the tomato sauce.
Add 1 more cup of stock to the blender with the remaining sauce ingredients and purée for 2 minutes. This mixture, too, will become smooth but a little grainy. Pour it into the bowl and stir together.
Wipe out any tomato residue from the skillet and add the remaining oil. Warm the oil over medium heat. Spoon in the sauce and fry it for about 10 minutes, stirring up from the bottom constantly. Mix in the remaining stock and reserved chile cooking liquid, reduce the heat to low, and simmer for 30 minutes.
Divide sauce into two containers, as 1/2 will be enough for any recipe that serves 6 to 8. The sauce can be made ahead and refrigerated for 1 or 2 days, or frozen for several months.
