Szechuan Beef

In a medium bowl, whisk together marinade ingredients except for steak until fully combined. Reserve half the marinade and set aside. Add steak to medium bowl and toss in the remaining marinade until evenly coated. Let marinate for 30 minutes, then drain and pat dry with a paper towel. In a large bowl, toss together cornstarch and marinated beef, shaking off any excess cornstarch before frying. In a large skillet over medium-high heat, heat 2 tablespoons oil. Add steak in a single layer, working in 3 separate batches if needed, and cook until seared, 1 to 2 minutes per side. Remove steak and set aside. Return skillet to medium heat. Heat remaining 1 tablespoon oil, then add bean paste, dried chilis, peppercorns, garlic, green onion, and a pinch salt. Stir and cook until fragrant, 1 to 2 minutes. Add in chili oil and vegetables and cook, stirring occasionally, until slightly softened, about 4 minutes. Add in broth and let cook, stirring occasionally, until tender, 3 to 4 minutes more. Add hoisin, sambal oelek, and reserved marinade. Stir to evenly distribute, and bring to a simmer. Add back cooked steak and toss until evenly coated. Let cook, stirring, until sauce thickens and clings to the steak. Remove from heat and stir in sesame oil and vinegar. Garnish with sesame seeds and more green onions before serving.