Pork & shitake pot stickers

This recipe is found in cooking light and can be found here. Though they are a lot of work, they freeze great (I have about 30 in the freezer) and are easy to pop out and cook. These are very tasty and fun.

Ingredients

• 
  2 tablespoons dark sesame oil
• 3/4 cup thinly sliced green onions, divided
• 1 tablespoon minced garlic
• 1 tablespoon grated peeled fresh ginger
• 4 ounces thinly sliced shiitake mushroom caps
• 5 tablespoons lower-sodium soy sauce, divided
• 1 tablespoon hoisin sauce
• 1/2 teaspoon freshly ground black pepper
• 14 ounces lean ground pork
• 40 gyoza skins or round wonton wrappers
• Cornstarch
• 1/4 cup hot water
• 2 tablespoons brown sugar
• 2 tablespoons rice wine vinegar 
• 1 1/2 tablespoons sambal oelek (ground fresh chile paste)--I didn't have this so I omitted 
• Cooking spray

1. 1. Heat a large skillet over high heat. Add sesame oil to pan; swirl to coat. Add 1/2 cup onions, garlic, ginger, and mushrooms; stir-fry 3 minutes. Remove from pan; cool slightly. Combine mushroom mixture, 1 tablespoon soy sauce, hoisin sauce, pepper, and pork (that's been browned in a sauté pan) in a medium bowl.
2. 2. Arrange 8 gyoza skins on a clean work surface; cover remaining skins with a damp towel to keep them from drying. Spoon about 1 1/2 teaspoons pork mixture in the center of each skin. Moisten edges of skin with water. Fold in half; press edges together with fingertips to seal. Place on a baking sheet sprinkled with cornstarch; cover to prevent drying. Repeat procedure with remaining gyoza skins and pork mixture.
3. 3. Combine 1/4 cup hot water and brown sugar in a small bowl, stirring until sugar dissolves. Add remaining 1/4 cup green onions, remaining 1/4 cup soy sauce, vinegar, and sambal, stirring with a whisk until well combined.
4. 4. Heat a large heavy skillet over high heat. Generously coat pan with cooking spray. Add 10 pot stickers to pan; cook 30 seconds or until browned on one side. Turn pot stickers over; carefully add 1/3 cup water to pan. Cover tightly; steam 4 minutes. Repeat procedure in batches with remaining pot stickers and more water, or follow freezing instructions. After cooking, serve pot stickers immediately with dipping sauce.
5. TO FREEZE: Freeze dumplings flat on a baking sheet sprinkled with corn­starch 10 minutes or until firm. Place in a large zip-top plastic freezer bag with 1 teaspoon cornstarch; toss. Freeze sauce in a small zip-top plastic freezer bag. Freeze up to 2 months.
6. TO THAW: Thaw sauce in the microwave at HIGH in 30-second increments. No need to thaw pot stickers.
7. TO REHEAT: Follow recipe instructions for cooking, placing frozen dumplings in pan and increasing steaming time by 2 minutes.