Clean the greens and tear into medium-size pieces.

In a large cast-iron Dutch oven (7 quarts or bigger), fry the salt pork over medium-high heat until cooked but not crisp. Add the greens, turning them over several times to coat with the pork drippings. Add the broth, sugar, and salt and pepper. (You can adjust the salt and pepper to taste by adding more during the last part of cooking, so don't go crazy at this point).

Reduce heat and cover the Dutch oven, simmering the greens very gently. Greens release liquid as they cook, but check occasionally to make sure the pan hasn't gone dry. You may have to add just enough water to keep it from scorching, but never cover the greens with water.