Two simple steps and you're on your way to some great tasting refried beans.
How to make authentic refried beans
Start with great tasting ingredients. Get the freshest possible dried pinto beans. Anything that has been sitting around in a bag for a few months, even dried, will not make for the best result. Plus, the older they are the longer it takes to soften them up. Make it easier on yourself while you make it tasty.
Then lay the beans out, remove any small pieces of gravel, and rinse well in a collander. Yes, dried pinto beans will sometimes come packaged with small pieces of dirt or rock, depending on the source you buy them from. It needn't ruin the taste and it doesn't necessarily indicate poor quality beans.
Step one requires softening up the beans. You have two basic ways to do that, either by boiling or using a pressure cooker. A pressure cooker takes a little less time and is a bit easier. But boiling is fine, too. In either case, place 2½ cups (about 1 lb) of beans in about 3 quarts of water, ensuring that it covers the beans a couple of inches. For boiling, boil about 2½ hours stirring occasionally. A pressure cooker will require only about half an hour.
With either method, examine the beans and look for the majority to slightly split the skin. That indicates that the beans have absorbed a lot of water and the skin has softened enough for the added pressure to slightly break the skin.
Then drain the beans in a colander and shake gently.
Add a small amount of water (about ¼ cup) to a cold iron frying pan and pour in the beans. Add a pinch of salt or other seasoning as desired. Good choices are a bit of chili powder or a small amount of garlic. Then mash the beans slightly with a potato masher. They should be lumpy, not perfectly smooth. Think of mashed potatoes that have not been mashed enough. That's just about right.
Now drain any excess water and add a bit of lard or canola oil to the pan. Heat the pan to a medium-high level. As the beans fry, continue mashing, but still not too vigorously. The beans should remain somewhat chunky. Too much mashing turns them into soup.
That's all there is to it!
Of course, there are a hundred tasty alternative recipes.
Some frijoles refritos recipes call for adding chunks of onion to the pan and sauteeing them before adding the beans. That's fine. Spice it up with a little bit of jalapeño if you want. For more spice, add more chili powder, but take care not to overwhelm the beans (or your tongue).
In some recipes the beans are soaked overnight. That may work, but it often leads to excessively smooth refried beans, especially if you start with fresh ingredients. Be sure that when soaking and boiling you skim off any gray scum that floats to the top as the beans are being prepared.
Now for the most important part. Eat and enjoy!