In a 12-inch skillet (I prefer cast iron), toast the dried ancho chiles over medium-high heat, stirring frequently, until fragrant, about 4-6 minutes. Reduce heat when chiles start to smoke. Transfer to food processor to cool. Do not wash skillet.
Add árbol chiles, cornmeal, oregano, coriander, cocoa and salt to food processor with toasted ancho chiles; process until finely ground, about 2 minutes.
With processor running, slowly add the chicken broth until a smooth paste forms, scraping down chile remnants as necessary. Transfer paste to small bowl.
Place onions into now empty processor and pulse until roughly chopped. Add jalapeños and garlic and pulse until a chunky salsa-like consistency.
Add 1/2 teaspoon olive oil to the skillet on medium-high heat and add the onion mixture. Cook down until moisture is gone and combine with pepper paste.
Let mixture cool completely before transferring to a storage container. Keep in the fridge for up to a week or in the freezer for a month for future use.