Roll into a ball, wrap in cling film and chill for 30 minutes. To make the beef taco filling, heat the oil in a large frying pan and cook the onion and peppers for 5 minutes, or until softened.
The meat is cooked in an adobo, a sauce made with chillies, spices and vinegar. The birria can be eaten in a bowl like a soup, or in tacos or quesadillas (see Tip). You can make the adobo a day ahead.
Taco Bell has spent two years perfecting the recipe, which I first got to try ... A creamy jalapeño sauce is drizzled inside, and the taco is also served with two dipping sauces — Taco Bell's ...