Make a roux by mixing the flour and butter over medium heat until combined, 3 to 5 minutes. Stir in the leeks and parsnips and cook for 5 to 7 minutes longer. Slowly whisk in the Ham Hock Stock. Bring to a boil, and then reduce to a simmer until thickened, stirring frequently to avoid burning, 20 to 30 minutes. Pour in the beer and bring back up to the point just before boiling. Don't let the beer come to a boil or it will taste bitter. Transfer the soup to a blender or food processor and puree in batches, gradually adding the cheese and cream. Pour all of the soup into a large container and season with salt, pepper and sugar. 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, we cannot make any representation as to the results.
Combine the onions, carrots, celery, parsley, thyme, peppercorns, leeks, ham hocks and 1 1/2 gallons water in a stockpot. Bring to a boil, and then reduce to a simmer and cook for 6 to 8 hours. Strain and reserve the liquid.