1 medium onion, peeled and halved
1 lb. dry pinto beans, rinsed and drained
½ fresh jalapeno pepper, seeded and chopped
3-4 cloves garlic, minced
1 TBS salt
1 teaspoon fresh ground black pepper
⅛ teaspoon ground cumin, optional
6 cups water
Place the onion, rinsed beans, jalapeno, garlic, salt, pepper, and cumin into a slow cooker. Pour in the water and stir to combine. Cook on High for 6-8 hours, adding more water as needed. Note: if more than 1 cup of water has evaporated during cooking, then the temperature is too high.
Once the beans have cooked, strain them, and reserve the liquid. Mash the beans with a potato masher, adding the reserved water as needed to attain desired consistency.
Adapted from https://www.allrecipes.com/recipe/70312/refried-beans-without-the-refry/