In a medium bowl, combine the chicken with the Shaoxing wine, mushroom-flavored dark soy sauce, garlic powder, and cayenne pepper. Marinate at room temperature for 15 minutes: if you're planning to marinate the chicken longer, cover it with plastic wrap and transfer it to the fridge overnight.
In a large ziplock bag, add cornstarch, cayenne powder, ground Sichuan pepper, and salt, and shake to mix well; set aside. Combine the spice mix ingredients in a separate medium bowl; set aside. In a small bowl, combine grated ginger, thinly sliced garlic, and chopped green onion; set aside.
Once marinated, drain the chicken pieces and discard the marinating liquid. Transfer the chicken pieces into the ziplock bag with the cornstarch mixture, seal, and shake until they are fully coated.
Heat 2 tablespoons of the peanut oil in a large wok or large nonstick skillet over medium-high heat; swirl to coat the wok. Once the oil is hot, spread out the chicken pieces without overlapping. Cook without touching the chicken until the bottom of the chicken turns golden brown around the edges, about 3 to 4 minutes.
Flip to cook the other side until golden brown. Stir a few times to ensure the chicken is cooked, and the center of the chicken registers 165 degrees F on an instant-read thermometer, about 3 to 4 more minutes.
Transfer with a slotted spoon to the prepared paper towel-lined plate and set aside. Wipe the wok out if needed. Return the wok to medium-high heat and add the remaining 2 tablespoons of oil to the wok. Just as the oil begins to smoke, stir in the garlic, ginger, and white parts of the scallions and stir-fry until fragrant, about 30 seconds.
Quickly add the spice mix and stir until the peppers turn a bit darker without turning black. Add the Sichuan Mala chicken back to the skillet. Add the scallion greens and toss until well combined.
Remove the pan from the stove and transfer everything to a plate with chili peppers. Top with cilantro for garnish. Serve hot over white rice.