Step one is to heat the sunflower oil up in a large pan. Fry the onions for 5 minutes and then add seasoning such as oregano and garlic, cooking for one to two minutes.
Stir sugar into the beef mixture, and then pour a little vinegar over it. If you aren’t planning on freezing your burritos, this is when you can add chopped tomatoes to the beef mixture and stir it in.
Fold over the ends of the burrito in order to seal them so that the filling doesn’t fall out. Serve immediately, or leave to cool if you wish to freeze them.