Instant Pot Refried Beans

1 pound dry pinto beans (picked over)

6 cups water

1 smoked ham hock

1 bunch of cilantro stems (see note)

½ sweet onion cut into four chunks

1 jalapeno pepper (optional)

1 tsp. coarsely ground black pepper

2-3 Tbsp. bacon drippings

1-2 tsp. salt (add after beans are cooked)