Heat a soup pot over medium-high heat and add sesame oil.

Add minced garlic and grated ginger; stir until fragrant (about 30 seconds).

Add chopped onion and shredded carrot with salt and pepper; cook until vegetables soften (about 5 minutes).

Add sliced mushrooms with salt and pepper; cook until they sweat and shrink (about 5-7 minutes).

Pour in beef broth, water, and soy sauce; stir to combine.

Bring to a boil, then reduce heat to low/medium-low and simmer for 20 minutes to intensify flavors.

Increase heat slightly; add ramen noodles and cook until al dente.

About 3 minutes before noodles are done, add bok choy; cook until wilted (about 1 minute).

Stir in miso paste (if using) and add an egg per person (optional); cook to desired doneness.

Taste and adjust seasoning with soy sauce, salt, or pepper; add miso before salt if needed.

Use tongs to transfer noodles to bowls, then ladle in broth and cooked egg.

Garnish with cilantro (optional) and serve.