Place the halved onion and ginger cut-side down in a dry pan over medium-high heat until charred and fragrant.
In a large pot, lightly toast the star anise, cinnamon stick, and cloves for 1-2 minutes.
Add the beef bone broth, charred onion, charred ginger, fish sauce, coconut aminos, and sea salt to the pot.
Bring to a boil, then reduce heat and simmer for 20 minutes to infuse the flavors.
While the broth simmers, cook the rice noodles according to package directions, drain, and set aside.
Place the eye of round steak in the freezer for 15 minutes to firm up, then slice it across the grain into paper-thin pieces.
Strain the broth to remove the solids and return the liquid to a rolling boil.
Divide the cooked noodles into a large bowl and top with the raw beef slices.
Pour the boiling broth directly over the beef to cook it instantly in the bowl.
Garnish with bean sprouts, Thai basil, cilantro, jalapeno slices, and a squeeze of lime before serving.