Creating Hunan Beef is straightforward if you follow these steps:

1. Prepare the Ingredients: Gather all your ingredients and slice the beef thinly against the grain.
2. Marinate the Beef: In a bowl, mix the sliced beef with soy sauce, oyster sauce, chili paste, rice vinegar, and a pinch of salt. Let it marinate for at least 10 minutes to absorb the flavors.
3. Heat the Oil: In a large skillet or wok, heat the vegetable oil over medium-high heat until shimmering.
4. Stir-Fry the Beef: Add the marinated beef to the skillet in a single layer. Stir-fry for about 3-4 minutes until browned but not fully cooked. Remove from the skillet and set aside.
5. Sauté Vegetables: In the same skillet, add onion, bell peppers, garlic, and ginger. Stir-fry for 2-3 minutes until the vegetables are tender-crisp.
6. Combine Ingredients: Return the beef to the skillet and stir everything together. Add hoisin sauce and sauté for an additional 2-3 minutes until the beef is fully cooked and well-coated.
7. Adjust Seasoning: Taste the dish and adjust with salt and pepper if necessary.
8. Garnish: Remove from heat and sprinkle chopped green onions and sesame seeds on top before serving.

These steps will help you create an incredible dish quickly and efficiently.