Fresh chorizo, without a casing, is simple to make. This recipe yields about three and a half pounds of the sausage—enough for this hearty potato dish, plus plenty leftover for topping eggs or filling tacos.
1. Make the chorizo: Heat both chiles in a 12″ skillet over medium-high heat; cook, turning, until toasted, about 5 minutes. Transfer chiles to a bowl and cover with 4 cups boiling water; let sit until soft, about 15 minutes. Drain chiles, reserving ¾ cup soaking liquid, and transfer to a blender along with reserved soaking liquid, cilantro, vinegar, paprika, salt, oregano, pepper, cumin, coriander, and garlic; purée until smooth. Transfer purée to a bowl and add pork and fatback; mix until combined. Cover with plastic wrap and refrigerate for up to 1 week.
2. Make the chorizo con papas: Bring a 6-qt. saucepan of water to a boil; add potatoes and cook until just tender, about 10 minutes. Drain and set aside. Heat 3 tbsp. oil in a 12″ skillet over medium-high heat. Add 1 lb. prepared chorizo, and cook, stirring to break up large chunks, until browned and fat renders, about 8 minutes. Transfer chorizo to a bowl and set aside. Add remaining oil to skillet, and then add reserved potatoes and onion; cook, stirring, until potatoes are browned and crusty, about 10 minutes. Stir in reserved chorizo; season with salt and pepper before serving.
FOR THE CHORIZO:
12 dried guajillo chiles, stemmed
8 dried chiles de árbol, stemmed
1 cup finely chopped cilantro
¼ cup apple cider vinegar
2 tbsp. paprika
2 tbsp. kosher salt
1½ tbsp. dried orégano, preferably Mexican
1 tbsp. ground black pepper
2 tsp. ground cumin
1 tsp. ground coriander
6 cloves garlic, finely chopped
2 lb. ground pork
8 oz. pork fatback, chilled and minced
2 lb. medium red-skinned potatoes, peeled and cut into 1″ pieces
⅓ cup canola oil
1 medium yellow onion, finely chopped
Kosher salt and freshly ground black pepper, to taste