Roast the beef bones and brisket in the oven at 400°F for about 30 minutes until browned.
In a large pot, add the roasted bones, brisket, halved onion, and ginger.
Cover with water and bring to a boil, then reduce to a simmer.
Add star anise, cinnamon, cloves, and coriander seeds to the pot.
Simmer for about 3 hours, skimming off any foam that rises to the surface.
Remove the brisket after 1.5 hours; set aside to cool.
Strain the broth through a fine-mesh sieve into another pot, discarding solids.
Thinly slice the brisket and add it back to the broth.
Prepare rice noodles according to package instructions.
To serve, place noodles in a bowl, ladle hot broth over them, and garnish with fresh herbs, lime, and jalapeños.