10 cups unsalted chick stock
1/2 lb pork hock, cut into 1 inch sections (can substitute should or loin)
1 yellow onion, peeled and halved
2 shallots, peeled and crushed
5 cloves of garlic, peeled and crushed
1/4 cup fish sauce
3 tbsp vegetable oil
1 tbsp black peppercorns
1 and 1/2 tbsp sugar
1/2 cup dried shrimp
Fresh thai chili finely chopped (can substitute fresh cayenne, jalapeno, or serrano pepper)
1 cup crab meat
6 cups cooked udon noodles
2 scallions, chopped
1/4 cup fried shallots
Bring the chicken stock to a boil in a large stock pot. Add the pork, onion, shallots, garlic, fish sauce, vegetable oil, black peppercorns, dried shrimp, chile, and sugar. Stir until the sugar is dissolved. Boil for around 20 minutes, then reduce to a simmer.
Carefully remove the pork from the simmering stock. Let it cool, then roughly chop the pork hock or, if using shoulder or loin, cut into slices. Set aside.
Add the crab meat to the stock and continue simmering for another 30 minutes. If you are not ready to serve, remove the pot from the heat.
Fifteen minutes before serving, bring the soup back to a boil. Divide the noodles into four bowls. Put the pork, scallions, and fried shallots on top of the noodles. Ladle the hot broth on top and serve immediately with a salad platter of quartered lime, fresh cilantro leaves, and fresh mung bean sprouts, to be added to the soup if desired.