Prepare the charred onion and ginger: Preheat the oven to 390°F (200°C).
Rub the onion and ginger halves with the sesame oil and place them onto a parchment lined baking tray with the cut sides facing up.
Bake in the oven for 35 minutes until charred. You will use this in your broth.
Prepare the spices. Add the star anise, whole cloves, cinnamon sticks, cardamon pods and whole coriander seeds into a spice infuser.
Prepare the broth: Add the vegetable stock/broth to a pot along with the sliced shiitake mushrooms and the roasted onion and ginger. Add in the infuser containing the spices.
Bring to the boil and then reduce heat, cover and simmer for 30 minutes. After 30 minutes of simmering, remove the spice infuser and then remove the roasted onion and ginger from the broth.
Add the coconut sugar, soy sauce, rice vinegar and sea salt and stir them into the broth.
Add the cubed tofu and baby bok choy and stir in. Simmer for another 5 minutes.
Prepare the noodles: Cook the rice noodles according to the package instructions.
Assemble the Pho: Ladle the broth over cooked rice noodles in a bowl.
Add fresh herbs and garnishes as you like.
Serve with a squeeze of lime.