Marinate the steak Freeze the New York Strip steaks briefly to firm them up, then slice against the grain into paper-thin strips. Toss with soy sauce, sesame oil, grated ginger, minced garlic, brown sugar, and red chili flakes. Set aside to marinate while you prepare the broth.
Build the broth Pour beef bone broth into a deep pot over medium heat. Add star anise, cinnamon stick, ginger, and garlic. Simmer gently until the spices bloom and the broth turns deeply aromatic.
Soft-boil the eggs Boil eggs for 6 minutes 30 seconds, then transfer immediately to an ice bath. Once cool, peel and slice in half. The yolk should be jammy and golden.
Finish the broth Remove the star anise and cinnamon. Whisk miso paste with a ladle of hot broth in a small bowl until smooth, then stir back into the pot.
Cook noodles and bok choy Cook ramen or udon noodles and divide into bowls. Blanch baby bok choy in the hot broth until just tender, then place on top of the noodles.
Flash-cook the steak Sear the marinated steak strips in a screaming hot skillet in a single layer, tossing once, until charred on the outside but still pink and tender inside.
Assemble and serve Ladle hot miso broth over the noodles. Fan the steak strips on top. Add the jammy egg halves. Finish with sliced spring onions, toasted sesame seeds, a squeeze of lime, and a generous drizzle of chili oil. Serve immediately!