1. Marinate the Beef: In a medium bowl, combine sliced beef with 1 tbsp soy sauce, 1 tbsp rice vinegar, 1 tbsp cornstarch, 1 tsp sesame oil, 1 tsp grated ginger, and 2 minced garlic cloves. Toss to coat. Let marinate for 15-20 minutes.

2. Prepare the Szechuan Sauce: In a small bowl, whisk together 3 tbsp soy sauce, 2 tbsp rice vinegar, 1-2 tbsp chili garlic sauce, 1 tbsp brown sugar, 1/4 cup broth, 1 tsp cornstarch, and 1 tsp ground Szechuan peppercorns until smooth. Set aside.

3. Chop Your Veggies: Thinly slice cabbage, bell pepper, and onion. Chop green onions for garnish.

4. Sear the Beef: Heat 1 tbsp oil in a large skillet or wok over high heat until shimmering. Add half the beef in a single layer; cook 1-2 minutes per side until browned. Remove and repeat with remaining beef, adding more oil if needed.

5. Stir-Fry the Vegetables: In the same hot pan, add a little more oil if needed. Add onion and bell pepper; stir-fry 2-3 minutes. Add cabbage; stir-fry 3-4 minutes until crisp-tender.

6. Combine and Sauce: Return beef to pan. Whisk sauce again and pour over beef and vegetables. Toss and cook 1-2 minutes until sauce thickens and coats everything.

7. Garnish and Serve: Remove from heat. Garnish with green onions and sesame seeds. Serve immediately over rice or noodles.