Cooking collards with a bit of healthy fat like olive oil may help the body absorb certain nutrients -- this hearty dish also features tomatoes and black-eyed peas.
In a large Dutch oven or heavy pot, heat oil over medium. Add onion and garlic and cook until onion softens, about 4 minutes. Add greens, cover, and cook until mostly wilted, about 4 minutes. Uncover and cook, stirring, until completely wilted, 2 minutes. Season with salt and pepper.
Add tomatoes, breaking them apart as you go. Add ham hock and 3 cups water and bring to a boil; reduce to a medium simmer. Partially cover and cook, stirring occasionally, until greens are tender and ham separates from bone, about 2 1/2 hours, adding more water if needed.
Remove ham from pot and let rest until cool enough to handle. Discard skin and bone; dice meat. Return ham to pot; stir in beans. Season with salt and pepper. Serve collards with rice.