Bring water, ham hock, sugar, paprika, garlic powder, onion powder, turmeric, celery seed, thyme and hot pepper vinegar to a boil in a stockpot. Cover, reduce heat to low and boil gently for 45 minutes, turning ham hock halfway through (it will not be covered by the water).
Meanwhile, in a non-stick skillet, heat olive oil and sauté onion for 5-6 minutes. Add garlic and sauté for another minute. Remove from heat and set aside.
At the 45-minute mark on the ham broth, remove ham hock and set it aside to cool (it interferes with stirring in the pot from this point on). Add onion mixture and collards to the boiling ham broth (add another cup of water if the liquid looks too meager for the collards), stir collards down into boiling liquid, cover, reduce heat to low and boil gently for 25 minutes. Add turnip pieces, making sure they are submerged in the broth, cover, and boil gently for another 20 minutes.
Meanwhile, when ham hock is cool enough to handle, chop it with a big knife and remove pockets of meat, adding the meat back into the pot. (This step may be omitted.)
Serve collards in bowls, making sure to get some turnip and some of the pot likker in each bowl.