Tear the greens into large pieces, wash under running water to clean well, drain.\
Preheat a heavy skillet with olive oil, add sliced onion and garlic; cook stirring frequently until onions begin to lightly brown, add minced jalapeño peppers.
Place the cooked onions in the bottom of the crockpot, add the drained greens, ham hock, crushed red pepper and water.
Cook on low for 5 to 6 hours or until greens are tender.
Remove meat from bones, discarding bone and fat.
Shred the meat and return to pot, mixing well; adjust salt and pepper to taste.
Top each serving of the greens with balsamic vinegar to taste.