Heat the vegetable oil and sesame oil in a large Dutch oven over medium heat.
Add the shallot and cook, stirring often, for 3-4 minutes, or until translucent and have started to soften.
Add the white portion of the green onion along with the ginger, garlic, and crushed red pepper flakes; cook, stirring constantly, for 1 minute.
Add the chicken broth and bring it to a simmer. Add the soy sauce, then cover with a lid and simmer for 10 minutes.
Add the sliced mushrooms, bok choy, and rice noodles to the pot; simmer for 6-8 minutes, or until the noodles and bok choy are tender. Taste and season, if needed.
Ladle into bowls, then top with the green onion and toasted sesame seeds, if desired. Serve immediately with chili oil and soy sauce on the side. Enjoy.
Side Note: The rice noodles eventually will soak up all the extra broth, so if you aren't serving the whole pot right away, I recommend you cook the rice noodles separately according to the package instructions and add them to the leftover soup when serving.