Step 1

Soak black beans in 6 to 8 cups of water, 8 hours to overnight.

Step 2

Drain beans. Place in a saucepan and cover with fresh water; add 2 teaspoons salt and bring to a boil. Cook until nearly tender, about 40 minutes.

Step 3

Combine remaining salt, onion, bell pepper, tomato sauce, garlic, olive oil, bay leaf, and cumin in a slow cooker. Add black beans and the cooking water.

Step 4

Mix well and cook on Low until the beans are tender and cooked through, 4 to 6 hours.