I found the "Perfect Potstickers {recipe} from scratch!" - including Dumpling Dough - on Pinterest and we were amazed by the result... they are excellent!
I am following the dumpling dough recipe to the letter and use my pasta attachment to roll the dough as thinly as I would dare (number 6 on KitchenAid). I understand that ideally you would roll them by hand in order to produce thicker middle where you need strength to support the filing and thinner edges where the dough is folded. But hey, I am happy enough with the uniformity of the pasta machine. I then cut circles with a scone cutter (hence the fluted look of mines). This dough is sticky enough that you don't need further water to make the edges stick together. I keep my bench floured with corn flour as it does not get absorbed by the pasta dough.
As filing, minced pork seasoned with ginger, shallots, soya sauce, teriyaki sauce and Char Siu sauce. Nothing precise; I am aiming for having salty + sweet + vinegary / rice wine components.
Cooking is easy: fry the dumplings in a couple of tsp of neutral oil until their bottoms are brown. Add to the pan about 100mL of water and cover immediately for 5-7 minutes. The dipping sauce is making them all shine and come together. Just oil, soya sauce, teriyaki sauce, Char Siu sauce and chilli flakes or powder. We love them!