Start by thoroughly washing the vegetables. Bring a large pot of water to a boil and blanch the vegetables just until wilted, about 60-90 seconds. Drain and rinse in cold water.
Grab a good clump of veg and carefully squeeze out as much water as you can. Very finely chop the vegetables (you can also speed up the process by throwing them in the food processor). Repeat until all the vegetables are chopped.
In a medium bowl, add the finely chopped vegetables, ground pork, 2 1/2 tablespoons sesame oil, pinch of white pepper, 1 tablespoon soy sauce, 1/2 teaspoon salt, and 1-2 tablespoons Shaoxing wine. Mix very thoroughly until the mixture is totally emulsified—almost like a paste.
Now it’s time to assemble! Fill a small bowl with water. Grab a wrapper and use your finger to moisten the edges of the wrapper. Add a little over a teaspoon of filling to the middle. Fold the wrapper in half and press the two sides together so you get a firm seal.
Hold the bottom two corners of the little rectangle you just made (the side where the filling is) and bring the two corners together. You can use a bit of water to make sure they stick. And that's it!
At this point, you can cook (boil) and taste a couple of wontons and adjust the seasoning of your filling to taste––you can always add a little more Shaoxing wine, soy sauce, sesame oil, salt, and/or white pepper to your liking.
Once you're happy with the flavor of the filling, keep assembling until all the filling is gone. Place the wontons on a baking sheet or plate lined with parchment paper, and make sure they are not touching (this will prevent sticking).
If you'd like to freeze your wontons right away, you can cover the wontons with plastic wrap, put the baking sheet/plate into the freezer, and transfer them to freezer bags once they’re frozen. They’ll keep for a couple of months in the freezer, and be ready for wonton soup whenever you want it.
To make the soup, heat your chicken stock to a simmer and add 2-3 teaspoons sesame oil and white pepper and salt to taste.
Bring a separate pot of water to a boil. Carefully add the wontons one at a time to the pot. Pick up the pot and use a swirling, twisting motion to keep the pot moving and prevent the wontons from sticking to the bottom. If they do stick, don’t worry, They should come free once they’re cooked. Once they're floating, boil them for another 1-2 minutes. Take care not to overcook them – mushy wontons are a sin! Remove the wontons with a slotted spoon and put them in bowls.
Pour the soup over the wontons and garnish with scallions. Serve!
Wontons can be frozen for use later. Lay them out on a baking sheet lined with parchment paper so they aren't touching, and put the baking sheet in the freezer. Once they're frozen, transfer them to a freezer bag and freeze for up to two months.