Heat the oil in a wok over a high heat and stir-fry the beef for 5-6 minutes until golden and crispy.
Add the garlic and the spring onion whites, and stir-fry for 30 seconds until fragrant.
Add the light soy and sesame oil and mix well.
Whilst the beef cooks, boil noodles for 2-3 minutes or until tender.
Scoop out some of the noodle water and drain well.
To make the sauce, mix the mayonnaise, gochujang and dark soy sauce.
Tip the noodles into the pan with the beef, add the sauce and 3-4 tbsp of the noodle water to make the sauce go creamy and cling to the noodles.
Stir-fry together and divide between two serving bowls.
Add the cucumber and scatter over the spring onions greens and sesame seeds.
