Soak the shiitake mushrooms in 1 cup of boiling hot water. Leave them soaking while you prepare the rest of the ingredients. Using a small blender or food processor, combine the silken tofu, vegan butter, and soy sauce, and blend until you have a smooth creamy paste.
Heat some vegetable oil over medium-high heat and add finely sliced spring onions, using only the white and light green parts.
Once the spring onions start to brown, add grated ginger and cook for another 1-2 minutes and then incorporate the miso paste and shiitake stock made with dried shiitakes. Dried shiitakes can sometimes release small hard bits during soaking; it's best to strain the shiitake broth through a mesh before adding it to the pot. Reserve the shiitakes for later.
Lower the heat and whisk all the ingredients until the miso paste has completely dissolved.
Incorporate the creamy silken tofu mixture into the pot, and then the vegetable broth. Whisk again, making sure all the ingredients are well combined, forming a smooth and silky broth.
Add the shiitake mushrooms finely chopped, and simmer for 5 minutes. At this point, you can also add edamame, peas, and corn.
Turn the heat off and enjoy with your favorite noodles and toppings.
To assemble the ramen bowl, first place your noodles in a big bowl. Then, pour the ramen broth while warm, and last, add your toppings.