In a large bowl, combine ground pork, shaoxing wine and light soy sauce. Mix well with a pair of chopsticks (or a fork). Add 4 tablespoons water to the mixture, 1 tablespoons at a time, and stir until the water is fully combined. The mixture should feel sticky and a bit runny, but still thick enough to coat a spoon. Add shrimp, shiitake, ginger, salt and black pepper, mix well.

Right before you’re ready to wrap the dumplings, add green onion and sesame oil, mix well.

Prepare a small bowl of water. Place a piece of parchment paper on a working surface or dust a wooden board with flour.

To wrap a potsticker, scoop about 2 teaspoons of the pork mixture and place in the center of the dumpling wrapper. Gently press the mixture into a round shape, so it will be easier to wrap. Wet your finger or a pair of chopsticks with water and gently brush water onto the edge of the wrapper (this will help the wrapper stick to itself when pressed together).

Fold the wrapper into a half moon shape, using fingers to pinch the middle and press the two layers together. Use your left hand to hold the dumpling and your right hand to fold 2 to 3 pleats in the outer layer towards the midpoint, and press it well to seal the filling inside.

Switch so that you're holding the dumpling in your right hand, and use your left hand to form more pleats in the same manner. Press the pleats again to seal the filling tightly. If you have trouble sealing the dumplings, reduce the amount of filling inside until you can seal it easily.

Place potsticker on the parchment paper. Continue forming the rest of the potstickers in the same manner. Leave about a finger’s width between any two dumplings, so they won’t stick together.

In a small bowl, drizzle vinegar over ginger slices. If the dipping sauce is not salty enough to your liking, you can add soy sauce to adjust the flavor, 1 teaspoon at a time.

Heat a tablespoon of oil in a nonstick skillet over medium high heat. When oil is hot, place potstickers in the skillet, pleat side up. Swirl 2 tablespoons water into the skillet, cover immediately, and turn the heat to medium.

Cook covered until the water is evaporated and potstickers are cooked through, about 3 minutes. Remove the cover and flip one potsticker to see whether the bottom side is charred. If not, turn to medium high heat and cook until the bottom side turns golden brown, about 1 minute. Transfer the potstickers to a plate.

Serve immediately with dipping sauce.

Store the cooked potstickers in an airtight container in the fridge for 2 days.

For uncooked potstickers, place them in a large airtight container, one finger’s width apart. Do not overlap dumplings. Store in freezer up to 1 month.

You don’t need to thaw the potstickers before cooking. Heat a tablespoon of oil until hot and place dumplings in one at a time. Swirl in 4 tablespoons water and cover. Cook over medium heat until cooked through, about 5 minutes. Remove the cover and flip one potsticker to see whether the bottom side is charred. If not, turn to medium high heat and cook until the bottom side turns golden brown, about 1 minute.