I don't bother with stuffing the chorizo into skins, I just either make into thin burgers (as a topping for a regular burger ) or shape into meatballs, snags or just use as normal mince.
Minced Pork - Shoulder preferably
Fresh Garlic - Pounded to a puree
Fennel Seeds - Crushed
Salt
Dried Chillies - Ground OR Pickled Red Bell Chillies, seeds removed and pounded to a puree
Smoked Paprika
Pepper
Red Wine OR Red Wine Vinegar OR a mix of both
Mix everything together and leave in the fridge for at least a couple of days for the flavours to marry up...the longer the better BUT there is no cure in my recipe, it is FRESH so use up before the "Best Before" date of your pork!!!!