Preheat oven to 200'C fan/220'C conventional
Brush your portobellos with oil and season lightly with salt. Place stem-side up on a wire rack and place the rack within an oven tray. This will allow the water released by the mushrooms to collect at the base of the tray without the mushrooms swimming in it. Roast for 10-12 mins
Place a pan on medium heat, add your oil, shallot, and garlic. Sauté until fragrant and shallot has softened
Add in your crumbled tofu and continue to cook until no water remains
Add in your shiitakes and sauté for a further 1min
Add your miso, dark soy, and a pinch of white pepper
Finally, mix your flour and water to form a slurry and add this into the mushroom mix. Cook on a high heat for 1 minute. Place aside and allow to cool slightly
Tip your portobellos over to drain out any water, fill each with around 2tbsps of filling, top with black and white sesame, and drizzle lightly with oil
Turn the oven down to 170c and place the stuffed mushrooms back in for 15 minutes or until the filling has crisped up
Garnish with spring onions and small pieces of toasted nori
Best served immediately