Vietnamese Pork Noodle Soup Recipe - Hủ TiếU Mì

Blanch the bones: To ensure the pot is large enough to blanch the bones without boiling over, put the bones in the pot and add water to cover by 1 inch. Then remove the bones and bring the water to a boil. When it is at a rolling boil, add half of the pork bones, return the water to a boil, and boil for 5 minutes.
With a spider or tongs, remove the first batch of bones from the water and place in a colander. Return the water to a boil and repeat with remaining pork bones. When all the bones have been blanched, rinse under cold running water. Rinse the pot and return the bones to the pot.
Add the trotter, onion, white peppercorns, salt, and 6 quarts of cold water to the pot and bring to a boil over high heat, skimming off any scum that forms on the surface. Lower the heat so the liquid is at a gentle simmer and simmer for 2 hours, skimming as needed to remove any scum that forms on the surface.
Remove from the heat and, using a spider or a slotted spoon, discard the large solids. Strain the stock through a fine-mesh sieve into a large container, let sit for a few minutes (or refrigerate overnight), then skim most of the fat from the surface (leave some, as it gives the stock a better flavor and mouthfeel). Use immediately, or let cool completely, then transfer to practical-size airtight container and refrigerate for up to 3 days or freeze for up to 3 months.