Sort and rinse the dried black beans.
Place the beans in a large bowl and cover with 8 cups or enough water to cover the beans with at least 1” of water. Soak for 8 hours or overnight.
When ready to cook, drain the soaked beans and set aside.
Add the olive oil to a large pot over medium heat. Add the diced onion, minced garlic, and cumin. Sauté until the onion is translucent for about 4 minutes.
Add the drained beans and cook for 5 minutes.
Add the smoked ham hock, chicken stock, 1 teaspoon of Kosher salt, and a pinch of black pepper to the pot. Simmer on low heat for 1-2 hours, or until the beans are cooked through and tender.
Stir the beans every 20 minutes and add more chicken stock or water as needed to achieve the desired texture. Taste and season with additional Kosher salt and pepper if needed.
Top with sliced green onions and serve.