For years I've made my tacos with ground beef and potatoes. This recipe is not made with store-bought chorizo, but ground pork to which you add the spices, so you get to control the heat. Recipe from Saveur.
In a large saucepan, cover the potatoes with 4 inches of cold water and bring to a boil. Simmer over low heat for about 30 minutes, until tender. Drain and let cool slightly. Peel the potatoes and coarsely mash them in the saucepan.
In a large bowl, knead the pork with the salt, garlic, paprika, chipotles, coriander, oregano and vinegar. Gently knead in the potatoes, leaving some chunks of potato.
In 2 large skillets, preferably cast-iron or nonstick, heat the oil until shimmering. Add the chorizo-potato mixture to the skillets and press into an even layer. Cook over moderately high heat undisturbed until a crust forms on the bottom, about 5 minutes. Turn the mixture in sections and cook until browned and crusty on the bottom, about 5 minutes longer.
Transfer the chorizo-potato mixture to a bowl and serve with the tortillas, salsa, onion, cilantro and lime wedges.