If you are using frozen wrappers, they need to be completely thawed before using them. You can do so by leaving them at room temperature for a few hours.
Place the glass noodle in a medium size bowl and the dried mushrooms in another separate bowl. Fill both bowls with warm water to hydrate the ingredients,
The glass noodles won't take longer than 8-10 minutes, when they have softened, drain the water, cut using scissors into smaller pieces, and set aside.
The dried mushrooms will need to be soaked for at least 15 minutes. Then drain and set aside.
Cut the fresh vegetables. Thinly slice the onion, garlic, carrots, and cabbage.
When the mushrooms are ready, squeeze all the water out and slice them into thin strips as well.
Heat some oil in a wok or large frying pan over medium-high heat.
Add the onion and sautée for 1-2 minutes. Then add the garlic. Stir for 1-2 minutes making sure it doesn't burn.
Add mushrooms, sautée for 2-3 minutes, and then add the cabbage and carrot. Cook for about 4 minutes or until the carrot starts to soften.
Add white pepper, vegan oyster sauce, and a pinch of salt. Stir well. If you are using soy sauce instead of vegan oyster sauce, you may need to add some cornstarch slurry at this point.
Make some space in the center of the wok or pan and add the vermicelli or glass noodles. Mix well making sure the noodles absorb all the extra moisture.
Add the sesame oil, stir one last time, and turn off the heat.
Leave the filling to cool for about 15 minutes.