Wipe off any dusty crevasses on the dried chiles. De-stem and de-seed the chiles, but don't worry about getting rid of every last seed.
Roast the chile pieces for 1-2 minutes in a 400F oven. Alternatively, you can flash roast them in a skillet on the stovetop for 15-30 seconds per side. Once roasted, add them to a bowl and cover with hot tap water. Let the chiles reconstitute for 20-30 minutes. If they float to the surface you can use a small bowl or plate to keep them submerged.
Rinse and de-stem 7-8 Roma tomatoes. Roast the tomatoes in a 400F oven for 20-30 minutes.
Roughly chop an onion and peel 8 garlic cloves. Add a glug of oil to a skillet over medium heat and saute the onions and whole garlic cloves until lightly browned. Once cooked, add the onion-garlic mixture to the blender.
Preheat a dry skillet over medium heat. Add 2/3 cup sesame seeds, 8 whole cloves, and 12 black peppercorns to the skillet. Toast until the sesame seeds are turning golden brown, stirring occasionally. Towards the end, add the powdered spices to the skillet (2 tablespoons cinnamon, 1 tablespoon Mexican oregano) and cook briefly. Add the mixture to a food processor or spice grinder and grind into a fine powder, setting it aside until you need it.
By now the chiles are reconstituted. Take a taste of the chiles' soaking liquid. If you like it then you can use it to liquefy the sauce. If it tastes bitter to you then use stock to liquefy the sauce -- I used stock for this batch.
Drain the dried chiles and add them to the blender along with a cup of stock (or soaking liquid). The onion-garlic mixture should already be in the blender. Combine well. It's worth it to take a taste at every step along the way, starting now!
Add the roasted tomatoes to the blender and combine well. This should all fit in a single blender jar, but you may have to blend the tomatoes in batches.
Add the finely ground spice mixture to the blender and combine well. I also added another cup of stock at this point. You'll need 3-4 cups total for the recipe -- I usually just keep track of what I add when blending and then add the rest for the simmer.
Add 2 tablespoons raisins, 1/2 cup almonds and 1 teaspoon salt. Combine well.
Add 2 tablespoons lard (or oil) to a large saucepan. Once heated, add the Coloradito sauce from the blender to the saucepan and simmer until heated through. Use a splatter screen if you have one, otherwise a layer of parchment paper or foil will do the job.
Once heated through add 2 oz. chocolate (optional). I used 1/3 cup semi-sweet chocolate chips, but you can use Mexican chocolate if you want.
Once the chocolate is incorporated into the sauce take a final taste for seasoning. I added another generous pinch of salt to this batch. (So that is about 1.5 teaspoons salt total but keep in mind this will depend on which stock you use.)
You can optionally strain the Coloradito sauce at this point. Place a fine mesh sieve over a bowl and use a spatula to force the sauce through the strainer. Be sure to wipe the bottom of the strainer as the sauce tends to cling to it.
Optional serving style: warm 10-12 corn tortillas in the oven (or flash fry them). Use tongs to dredge them in the Coloradito sauce. Add Queso Fresco and finely chopped raw onion to the tortillas, then fold in half and drench them with more of the Coloradito sauce. Serve immediately with optional garnishes: toasted sesame seeds, Mexican Crema, more Queso Fresco, and freshly chopped cilantro.
Store leftover Coloradito sauce in an airtight container in the fridge.