Fry bacon until crisp then remove from pot. Add onion and saute until translucent.
Place ham hocks, bay leaves, red pepper flakes, and sugar in a large pot with the chicken stock. Bring to a boil, reduce heat to simmer, and cook for 2 hours.
Stir greens into the pot, and bring to a boil. Reduce heat to simmer, and cook for 60 minutes, or until greens are tender. Season with nutmeg and vinegar add salt and pepper to taste.Add bacon to hot greens before serving.