Cook chorizo in a large saucepan over medium heat until beginning to brown, 3 to 5 minutes. Add onion; cook, stirring often, until softened, about 3 minutes. Stir in tomato, chiles, cumin and pepper; cook, stirring occasionally, until the tomato begins to break down, about 3 minutes. Pour in beer, increase heat to medium-high, and bring to a boil, scraping up any browned bits.

Stir in mussels and return to a simmer. Cover, reduce heat to medium-low, and cook just until the mussels have opened, about 7 minutes. Remove from the heat and stir in cilantro. (Discard any unopened mussels.) Serve the mussels with the sauce.

Ingredient note: For this recipe we use fully cooked Spanish-style chorizo--spicy pork sausage seasoned with smoked paprika and chile--recognizable for its characteristic red color. Find it near other cured sausages in well-stocked supermarkets, specialty-food stores or online at tienda.com.

Tip: To clean mussels, scrub with a stiff brush under cold running water. Scrape off any barnacles using the shell of another mussel. Pull off the fuzzy "beard" from each one (some mussels may not have a beard).