Prepare the potsticker wrappers (hot water dough):

Form a dough and knead until elastic.
Pour 1/2 cup hot water (about 160°F/70°C) into a bowl with the flour and mix. Add 2 3/4 tablespoons cold water and mix until the flour and water are fully combined. Knead until the dough is smooth, not sticky, and elastic. It doesn't need to be perfectly smooth.

Let the dough rest for about 15 minutes.
Place the dough in a plastic bag and let it rest for 15 minutes. After resting, the dough will be softer and easier to roll out. While waiting, you can prepare the filling.

Roll out the wrappers.
Sprinkle the work surface with flour to prevent sticking. Place your left thumb in the center of the disc and hold the edge with your fingers. Use a rolling pin with your right hand to roll from the edge toward the center, stopping at the middle. Rotate the dough about 60-90 degrees and repeat, rolling and rotating until you have a round wrapper. Repeat with all dough pieces to make potsticker wrappers.

Prepare the filling:
Finely chop the cabbage and drain excess water.
Chop the cabbage into small pieces and place in a bowl. Add 1 teaspoon salt and mix by hand for about 1 1/2 minutes to draw out moisture. Squeeze out the excess water and set aside.

Combine all filling ingredients in order.
Add the mixed seasonings to the sticky ground pork and mix well. Add the green onions and mix. Add the drained cabbage and mix until well combined. The filling is now ready.

Seal the wrappers.
Moisten the edge of the wrapper with water, fold in half, and seal the top, leaving the sides open for now.
Shape the potstickers.
Place the half-sealed potsticker on the work surface. Pinch the sealed edge on both sides and gently pull outward, then press down to seal. This will give your potstickers a nice, plump shape.

Pan-fry the potstickers:
Heat 1 tablespoon oil in a nonstick skillet over medium-high heat. Arrange the potstickers closely together in the pan so they stick together when cooked. Pour the flour-water slurry over the potstickers. Once it comes to a boil, reduce to medium-low heat and cover with a lid (preferably glass so you can see inside). Do not lift the lid during cooking to keep the steam in and prevent the wrappers from drying out. When the bottoms are golden and crispy, turn off the heat. Place a plate over the pan and invert so the crispy bottoms face up. Serve immediately!