Preheat the oven to 300° F (150° C). Line a baking sheet with parchment paper.
Break the dried shiitake mushroom into small pieces and add them to a food processor. Run the processor until the shiitake is roughly ground up.
3 grams dried shiitake mushroom
Add the rolled oats and grind the mixture until you have a coarse meal. If you don't have a food processor, you can crush the oatmeal with your fingers and use a Microplane to grate the shiitake into a powder.
50 grams rolled oats
Transfer the ground oats into a bowl and add the sesame seeds.
20 grams toasted sesame seeds
In a separate bowl, whisk together the brown sugar, soy sauce, salt, konbu cha, and vegetable oil until the ingredients are evenly dissolved.
11 grams brown sugar, 1 tablespoon soy sauce, 1/2 teaspoon salt, 3 grams konbu cha, 1 tablespoon vegetable oil
Pour the seasoning over the oats and stir together until the mixture resembles wet sand.
Dump this mixture onto your parchment-lined baking sheet and spread it out into a thin, even layer. Bake the Furikake for 15 minutes, stirring it once midway through.
Once the Furikake is dry and crisp, remove it from the oven and let it cool to room temperature. Use a rolling pin to break up any large clusters.
Transfer the mixture to a bowl and then mix it with the aonori and matcha.
2 teaspoons aonori, 1 teaspoon matcha powder
Transfer the Furikake to a bowl and mix in the aonori and matcha. Store your vegan Furikake in a sealed container.