My mum has always made these and there are many variations you can make. I used pork mince, spring onions, grated carrot and I marinated the mixture with ginger wine, corn flour, some chinese spice and salt and white pepper. I let it marinade for about 15 to 20mins and then I added the egg to the mixture. The bowl on the left is the mixture with egg and the bowl on the right is mixture without. I then fried these into small omelettes. I prefer them small but some people do make one large one. Once they are fried and cooled I will bag them up for the freezer. I like mine with worcester sauce and tomato ketchup. These can be eaten with a bowl of rice, congee or soup noodles, just heat up in the microwave for a few minutes from frozen.
Vanessa Wong recently added fresh coriander to her dan gwok. It is also possible to use small cubed meat instead of mince but marinade them in the same way.
I also like to add green beans diced in small pieces, it gives it a nice crunch.