Make Marinade: Mix the marinade ingredients—soy sauce, black pepper and cornstarch—in a bowl. Add shrimp and set aside.
Make Sauce: Mix the sauce ingredients in a bowl and set aside.
Sauté peanuts: Add 1 tablespoon of oil to a wok or frying pan and heat to medium. Add Sichuan peppercorn (or red pepper flakes) and peanuts and stir-fry until peanuts are golden (about 2 minutes). Remove peanuts and pepper flakes to a bowl.
Sauté Shrimp: Add 1 tablespoon of oil to the pan and bring heat to medium-high. Add shrimp in a single layer and cook just until pink on the bottom, about 2 minutes. Flip and cook on the other side for 1-2 minutes. Remove to bowl with peanuts.
Sauté Veggies: Add final tablespoon of oil to pan over medium high heat. Add ginger, garlic, green onion, bell peppers, onion (any additional vegetables) and szechuan pepper if desired. Stir-fry for 1-2 minutes.
Combine: Add the reserved sauce and cook until the sauce begins to slightly thicken. Stir in shrimp and peanuts and toss to combine.
Serve immediately with a side of hot cooked white rice or fried rice.
