My mum would go marketing every Saturday and when I followed her, we would always order beef hor fun at the adjoining hawker center. I was very sad when we moved. If you don't like beef, use pork or chicken.
Toss beef with 1 tablespoon corn flour, 1 teaspoon sesame oil and 1 teaspoon Chinese wine, and set aside to marinate.
In a small bowl, combine remaining corn flour with 2 tablespoons water and mix into a slurry.
In a large wok, heat 2 tablespoons oil until smoking hot. Add the hor fun and stir fry until golden brown, about 2 to 3 minutes. Add the dark soya sauce and stir fry for another 2 minutes to evenly colour. Turn onto a serving platter.
In the same wok, heat the remaining oil over high heat until it shimmers. Add the garlic and beef and stir and cook for 1 minute. It's ok if the meat is still pink.
Add the water. Stir in the remaining soya sauce, Chinese wine, sesame oil, and oyster sauce, and sugar, and mix well. Bring to a boil.
Pour in the corn flour slurry to thicken the gravy, stirring constantly. Add the kai lan and cook for about 2 minutes, or until it thickens.
Pour the gravy over the hor fun and sprinkle with pepper. Serve immediately with pickled green chillies and soya sauce.