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 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. Remove the onion and jalapeno.
Mash the beans with a potato masher, adding the
reserved water as needed to attain desired