In one deep skillet, at medium heat, add the sliced onions and peeled garlic cloves. Drizzle in enough oil to lightly coat ingredients. Saute, turning as needed until you have some light caramelization.
In the second pan, add the dried chiles. Drizzle with a light coat of oil. When the chiles begin to sizzle and are slightly aromatic, stir and flip them over often for the next 1-2 minutes.
Add the chiles to the pan with the onions and garlic.
Sauté for 30 seconds. Pour in 3 cups of water. Bring up to a light simmer and cook for 10 minutes. Cover, remove from the heat and let sit for 15 minutes.
Transfer all the ingredients to the blender, including all the water in the pan. Pour in the reserved 2 cups of water and all the spices. Blend on high until very smooth. If you are not using a power blender, I would recommend you strain the sauce. Pour salsa/sauce into ¼ cup of preheated pork lard or oil. Continue cooking at a light simmer for 20 minutes. Taste for salt as it cooks.