How can I get the smokey flavour in Hor Fun? I made Hor Fun (not the linked recipe in specific) the other day for my girlfriend who loves the dish. However, her critique was that it lacked the distinctive smokey flavour of the dish.

When it's made traditionally it's done over a massive fire and this gives it the smokey flavour.

In a standard kitchen the gas burners are far smaller than that, so how can I achieve the same smokey flavour for this dish?
Another option is Smoked Paprika. As Jolene wisely cautions, those liquid smoke products are very strong. And even though it might be "natural" smoke flavor, it can lend a "synthetic" taste to delicate foods.

Smoked Paprika has a much more subtle smokiness. Of course, it will also add color and additional flavor of its own. It sounds to me like this would work well with the recipe you linked, but you might try adding it first to just a small amount of your dish and see if you like the taste.

In any case, Smoked Paprika is an inexpensive addition to your spice rack that can be used to enhance many foods with a bit of smokey flavor.