Bring 5 cups of chicken stock to a boil in a saucepan and then transfer off of the heat
Remove the stems and seeds from the dried chilies
Submerge the dried chilies and prunes in the hot stock and set aside for 30 minutes to rehydrate
Preheat your oven to 400 degrees
Place a large quartered yellow onion and 6 halved roma tomatoes on a baking sheet and roast at 400 degrees until softened and charred, about 20 minutes and then set aside for now
Place a large cast iron skillet over medium heat and add 1/3 cup of sesame seeds, 6 whole cloves, 1 teaspoon of aniseeds and 1/2 teaspoon of whole peppercorns into the hot, dry skillet and toast the spices while stirring consistently until the sesame seeds have become lightly golden brown
Add a teaspoon of ground cinnamon, a teaspoon of cumin and a teaspoon of Mexican oregano and toast for another 60 seconds or so
Transfer the spices into a spice grinder or mortar and pestle and grind until fine
In a large blender, combine the roasted onion and tomatoes, the rehydrated chilies and prunes (including most of the stock), 8 cloves of roughly chopped garlic, the finely ground spices and 1/2 cup of almonds and blend until smooth. Add the remaining stock to thin if necessary.
Optionally, strain the mixture and transfer into a large skillet over medium low heat
Bring the sauce to a low simmer and add 2 tablespoons of butter, 2 ounces of roughly chopped Mexican chocolate and a generous pinch of sea salt
Simmer the mole sauce and add additional stock if thinning is desired
If the mole is more spicy than you prefer, add a tablespoon or two of fresh lime juice or white vinegar to reduce the heat