I just know the name. I don't know why they are called that. I bought a tin once to serve with some chilli sin charne as I had heard that this is the Mexican thing to do. When I got home and opened the tin, I realised I had just about paid four times the going rate for a tin of pinto beans. Okay, they were mashed up and a bit of onion and a few spices had been added, but you can do that yourself in five minutes.
If you make up a heap of refried beans, the leftovers are great served cold as a pate - good for picnics
Chop the onion and fry in vegetable oil until it begins to brown. Add the garlic (crushed or chopped), and the spices. Stir and after a minute, add the drained beans. Continue cooking and stirring for a few minutes to warm the beans then mash all the ingredients while the pan is still over the heat. Add a litle hot water from the kettle if the mixture is too thick.
Refried beans are good as part of a Mexican-themed spread, served along with chilli sin carne, guacamole, tomato and green corriander salsa and taco shells (and don't forget the tequilla).