In a bowl, mix shrimp, cornstarch, coriander and sesame oil. In a hot wok, coat with canola oil, and quickly stir-fry the shrimp for only 2 minutes keeping them rare. Set aside. In the same wok, add a little more oil and caramelize garlic, ginger and onions. Season. Add mushrooms, oyster sauce and chicken stock. Add noodles, haricots and shrimp. Quickly heat up and serve immediately.