In a large pot combine the ham hock, onion, extra-virgin olive oil, and smashed garlic. Add the water and bring to a simmer over medium heat. Simmer for 1 hour.
Gradually add the collard greens to the stock pot. You will have to add the greens in stages to allow time for them to boil down. Once all your greens have been added, lower your flame to a soft boil, and allow them to cook until tender, about 55 minutes.
Professional Recipe: This recipe was provided by a chef, restaurant or culinary professional and makes a large quantity. The Food Network Kitchens chefs have not tested this recipe in the proportions indicated and therefore cannot make any representation as to the results.