Soak the beans (optional to cut cooking time)

• Rinse the beans thoroughly under running water and place in a large bowl. Add enough water to cover them by at least 2 inches. Set aside to soak at room temperature for at least 3 hours and up to overnight.
• Stove top directions:
• When ready to cook, drain the soaked beans and rinse them again under running water.
• In a large 4-quart pot, Mexican olla, or dutch oven, add the beans, 8 cups water, garlic and onion.
• Bring to a boil over high heat, then reduce to a low simmer.  
• Reduce heat to medium-low and cook for 2 hours or until soft and can break easily with a spoon
• Using a bean/potato masher, smash the beans to form a chunky puree - alternative, use a stick blender to make a smoother puree. 
• Add the 1 tablespoon of salt.  
• In a small skillet, heat the oil or lard until shimmering over medium-high heat.   
• Add the hot oil slowly to the beans (being careful not splash the oil outside of the pot) and mix well until it's integrated into the beans. 
• Cook for another 10 minutes on low. 
• Slow-cooker directions:
• Rinse beans. 
• Place beans in a 4-quart slow cooker with 6 cups of water. 
• Cover and cook on high for 4 to 5 hours or low for 8 to 10.
• Once the beans are soft and can break easily with a spoon, add the 1 tablespoon of salt.  
• In a small skillet, heat the oil or lard until shimmering over medium-high heat.   
• Add the hot oil to the beans and mix well until it's integrated into the beans. 
• Using a bean/potato masher, smash the beans to form a chunky puree - alternative, use a stick blender to make a smoother puree. 
• Cook for another 30 minutes on high.