best collard greens i've had were at ruby's bbq - now closed down. recipe i found for them:
1 ham hock
2 teaspoons cayenne
3 bunches collard greens, cleaned and torn or cut into pieces
1 tablespoons cider vinegar
1 teaspoons salt
1 tablespoons sugar
3 tablespoons butter
1 medium onion, sliced
3 tablespoons garlic, minced
Use only fresh, unblemished, brightly colored greens. Discard any bruised or discolored leaves. Get rid of the heavy stems. Wash greens in several fresh water baths—the first two baths should be slightly warm to remove sand and grit effectively. The last bath should be cold. Always lift the greens from the water, never just drain off. Be sure to remove the main rib before tearing or cutting the leaves.
Scrub and clean the ham hocks with a vegetable brush under cold running water. Dust with 1 teaspoon cayenne. Place it in a large pot with cold water to cover. Cover and bring to a boil. Reduce heat and simmer until tender—about 45 minutes to 1 hour. Add more water if necessary. Meat should be very tender (not springy or tough) and about to fall from the bone.
When the ham hock is cooked, add the prepared greens, cider vinegar, salt, sugar and remaining teaspoon of cayenne to the pot.
Lower the heat and simmer until nearly tender, approximately 45–60 minutes. Stir occasionally and periodically check the greens for tenderness—they should tear easily with a fork when done. If undercooked, they will have a bitter taste and a chewy texture.
In a saucepan, or cast-iron skillet, heat the butter and add the onion. Cook slowly over low heat, covered, and stir often until the onion is well softened. Add the garlic and continue to cook until the mixture is slightly caramelized.
Add the caramelized onion and garlic to the greens, and cook another 10–15 minutes. When finished, remove the ham hock and, when cool enough to handle, tear or cut the meat into small bite-size pieces. Caution should be used to avoid getting any bone fragments or pieces into the greens. Add the meat back into the greens and stir to distribute.