Heat 1 tablespoon cooking oil in a large soup pot or Dutch oven over medium heat.

Add the ginger and garlic, and cook for 1 minute, stirring constantly until fragrant.

Add the sliced mushrooms and the white parts of the scallions, along with 1 tablespoon sesame oil. Cook for 2–3 minutes, stirring occasionally, until the mushrooms start to soften.

Stir in the shrimp and cook for 2 minutes, just until they begin to turn pink. They will finish cooking later in the broth.

Add the broth to the pot, cover, and bring it to a boil over medium-high heat (about 5 minutes). Once boiling, lower the heat and simmer for 5 minutes to allow the flavors to blend.

Stir in 2 tablespoons coconut aminos, 1 tablespoon sesame oil, garlic powder, salt, black pepper, and red pepper flakes (if using). Taste and adjust the flavor — add more coconut aminos or salt if desired.

Add the rice noodles directly into the simmering broth. Cook for 5–6 minutes, or according to package directions, until the noodles are tender but not mushy. Stir occasionally to keep them from sticking.

During the final 3 minutes of cooking, add the bok choy halves. Submerge the stems first for about 2–3 minutes, then push the leaves down into the soup and cook for another 1–2 minutes, until tender and bright green.

Turn off the heat and stir in the remaining 1 tablespoon sesame oil and 1 tablespoon coconut aminos to enhance the flavor.

Ladle the soup into bowls. Garnish with green scallion tops, sesame seeds, and a drizzle of chili oil for a little heat.