Step #1 To prepare dipping sauce, mix first 5 ingredients, stirring well with a whisk.
Step #2 To prepare dumplings, carrot, ginger, place mushrooms, & vinegar in a food processor/blender; pulse until coarsely sliced, onions, scraping sides.
Step #3 Combine mushroom mixture & egg whites In a large-ish bowl; add turkey, stirring until mixd.
Step #4 Working with 1 gyoza skin at a time (cover remaining skins to keep from drying), spoon about 1 tbsp turkey mixture into center of each skin.
Step #5 Moisten edges of skin with water.
Step #6 Fold in half, pinching edges together to seal.
Step #7 Place dumpling on a baking sheet (cover loosely with a towel to keep from drying).
Step #8 Repeat procedure with remaining skins & turkey mixture.
Step #9 Heat 1 tsp vegetable oil In a large-ish nonstick skillet over medium-high heat.
Step #10 Arrange half of dumplings in pan; cover & cook 5 mins or until lightly browned.