Prep your king oyster mushrooms by slicing the tops off. You should end up with just a cylindrical piece. Use a spoon to gently remove the center meat to create a bone-like shape. Reserve the removed meat.
Drizzle the mushroom stems with olive oil and season with salt and pepper. Use your hands to evenly coat the stems then broil in the over for 5-7 minutes or until lightly golden brown. Alternatively, airfry at 350 for 5 minutes or so, then set aside.
Make Mushroom Filling
Add butter to a pan over medium heat and once hot, add shallots. Sauté for 3-4 minutes, until tender, then add garlic and cook for another 2-3 minutes. Season with salt.
Add mushroom stem inner meat along with torn maitake mushrooms and thyme. Sauté to cook for 4-5 minutes, until the mushrooms are tender and fragrant.
Transfer the pan mixture into a blender or food processor along with vegan cream cheese and olive oil. Blend until smooth and season with salt and pepper to taste. The mixture should be smooth and spoonable but on the thicker side.
Fill Mushroom "Marrow"
Using a spoon or piping bag, fill the mushroom stems with the mushroom filling, taking care not to overfill it.
Place the filled mushroom stems on a heat safe surface and use a blowtorch to gently char.