Make the stir-fry sauce: In a small bowl, whisk together soy sauce, vinegar, sesame oil, sriracha, chili pepper, salt, and pepper. Set it aside.
Sauté aromatics: Heat oil in a large pan or wok over medium-high heat. Add the garlic and ginger and cook for 30 seconds, until fragrant.
Stir-fry the onion and vegetables: Add the onion and scallions. Cook for 3-4 minutes, until softened. Then, add the broccoli and bell peppers. Cook for another 5-7 minutes, until crisp-tender.
Add lentils: Push the vegetables to the side of the pan and add the cooked lentils. Stir-fry for 1-2 minutes to warm through.
Incorporate the sauce: Add the prepared stir-fry sauce to the pan and toss everything together to coat evenly. Cook for another 2-3 minutes until the sauce is heated through. Taste and adjust the seasonings.
Serve: Transfer the stir-fry to plates and top with garnishes. Enjoy!
Notes
Prepare all your ingredients before you start cooking. Having everything ready to go is the key to successful stir-frying.
Use a hot pan or wok to sear the vegetables quickly. This helps retain their crunch and vibrant color.
Mix the stir-fry sauce ingredients separately before adding them to the pan. This ensures an even distribution of flavors throughout the dish.