Place cabbage, carrots, mushrooms, waterchestnuts, green onion and ginger in a food processor and process until everything is finely minced. Remove and place in a large bowl.
Add turkey, soy sauce, rice wine and sesame oil. Mix together (your hands work well)
Mix together the slurry. Take one wrapper, spoon 1 tablespoon of the filling mixture onto the middle of the wrapper. Dip one finger into the slurry and “paint” the edges of the potsticker wrapper. Bring up the bottom side of the wrapper, fold in half, encasing all of the filling. Pinch the edges. Place on a tray, cover loosely with plastic wrap and repeat with rest of dumplings. Make sure that the dumplings do not touch each other.
To cook, you can use 2 methods:
1) Fill a steamer pot with 1-2 inches of water and bring to a boil. Place the potstickers in a steamer basket and cook for 5 minutes until the filling is cooked through. Remove and let cool a bit before serving.
2) Half-fill a large pot with water and bring to boil. When boiling, gently slide in 1/3 of the potstickers. When water returns to a boil, turn heat to a simmer and gently cook for 6-8 minutes. Remove with slotted spoon and repeat with remaining dumplings.