If following the meal plan, the rest of the pack of wraps will be used in other recipes, but they also freeze well. Standard 400g tins of chopped tomatoes are usually cheaper than the smaller tins ...
Start by making the enchilada sauce. Put the onion into a medium saucepan with the olive oil and cook over a low-medium heat for 7–8 minutes, or until soft and just starting to brown at the edges.