Prep the vegetables: Julienne the carrot, celery, and bell peppers. Thinly slice the cabbage and onion. Chop scallions. Mince garlic and ginger.
Heat the oil (high heat): Heat olive oil in a wide frying pan or wok over high heat until hot.
Fry aromatics (high heat): Add ginger, crushed garlic, and hot pepper (if using). Cook for 1–2 minutes until deep golden and fragrant. Remove the pepper if desired.
Cook onion (high heat): Add sliced onion, green seasoning, and minced garlic. Stir-fry for 1 minute until fragrant.
Add carrot (high heat): Add carrot and cook for 2 minutes, allowing it to soften slightly while maintaining structure.
Add remaining vegetables (high heat): Add celery, bell peppers, cabbage, scallions and thyme. Stir-fry for 3 minutes until just tender but still slightly crisp.
Finish and season (off heat): Drizzle sesame oil. Season with salt and black pepper. Toss well and remove from heat immediately to prevent overcooking.