For serving: queso fresco or shredded Monterey jack cheesediced tomatoes, diced red onion, chopped fresh cilantro, avocado (optional)
Place the pinto beans in a large colander. Thoroughly rinse them. Pick the beans over, removing any damaged or clearly misshapen beans and discarding them. Transfer the rinsed beans to a 6-quart or larger slow cooker.
Heat the oil in a medium nonstick skillet over medium-high heat. Once the oil is hot, add the onion, jalapeno, and 1/2 teaspoon salt. Sauté for 2 minutes, then add the garlic and let cook just until fragrant, about 30 seconds. Transfer to the slow cooker. Add the sautéed vegetables, bay leaves, cumin, oregano, cayenne, and remaining teaspoon salt. Pour the broth and water over the top.
Cover and cook on HIGH for 8 to 10 hours, until the beans are tender. All slow cookers are different and can heat things differently, so if yours tends to run hot, check it earlier on. Depending upon your model, there may be some liquid still in the slow cooker. Discard the bay leaves.
FOR REGULAR PINTO BEANS (not refried): Drain the liquid if you like, or leave the liquid in the crock pot and serve the beans with it (I like them a bit soupy over rice), or use a slotted spoon for serving and drain the beans at the end prior to storing. Taste and adjust seasoning as desired.
FOR REFRIED BEANS: Reserve 1 cup of the cooking liquid, drain the beans, and return them to the slow cooker (if you don't have that much liquid in your slow cooker, you can use regular water instead). With a potato masher or pastry cutter, mash the beans until they reach your desired consistency, adding some of the reserved liquid as needed. (You can also scoop the beans into a blender in batches and puree them that way—be sure to let the beans cool somewhat first so that they do not splatter). Taste and adjust seasoning as desired.
Sprinkle with any desired toppings, serve, and enjoy!
Refrigerate leftover beans or freeze for up to 3 months.
For easy portions: Let the beans cool COMPLETELY, then portion them into ziptop freezer bags labeled with the date. Seal the bags, removing as much air as possible, and squish the beans so that the bag lays flat. Freeze flat and remove from freezer as you need them. Let the beans thaw overnight in the refrigerator, then reheat gently on the stove with a splash of water or broth as needed to thin them back out.