I recommend cooking dried beans (pinto beans or black beans - like my Refried Black Beans) for this refried bean recipe, it's really easy to do in your slow cooker (see instructions below or use my Slow Cooker Pinto Beans recipe). And you'll want some fat in these to give them that creamy, smooth texture. I had some leftover bacon fat which infused these cooked beans with fabulous flavor. But stock or bean cooking liquid and non-hydrogenated lard or olive oil (for a vegan version) will also work well.