Heat a dry wok or large skillet over medium-high heat. Add 1/4 cup yacai and stir fry for 1-2 minutes to reduce moisture, until it becomes fluffy and does not clump. Remove yacai from the pan and set aside.
Return the pan over medium-high heat. Add 12 oz mushrooms to the dry pan (do NOT add oil). Allow the mushrooms to release their moisture and shrink in size, stirring occasionally. After the mushrooms stop releasing water, about 4-5 minutes. Add 2 tbsp high heat cooking oil and stir to coat the mushrooms. Continuously stir fry for 1-2 minutes, until the mushrooms brown. Add the yacai, 2 cloves garlic, 2 tsp ginger, scallion whites, and 1 pickled chili if using into the pan. Stir-fry for 30 seconds more to release their aroma.
Add in 1 cup chilis and stir fry for 1 minute more.
Stream in 1/2 tsp dark soy sauce and 1 Tbsp shaoxing wine, immediately stirring to distribute. Add 1/2 tsp granulated sugar and season with additional salt to taste.
Remove from heat and drizzle with 1 tsp Sichuan peppercorn oil, stirring to distribute. Transfer to a bowl and garnish with remaining scallion greens.Serve with steamed white rice.
