In a small bowl, mix together ground chicken, lemongrass paste, garlic, ginger, green onions, red bell pepper, cilantro, sesame oil, soy sauce, white pepper, rice vinegar, and salt. Stir until well combined.
Fill a small bowl with water and keep near working area.
Lay out 4 to 5 wonton wrappers on a working surface. Cover the wrappers you are not using with a damp cloth or damp paper towel. Place about 1 teaspoon of chicken mixture into center of each wrapper.
Dip a finger into water and run it around all four edges of the wrappers. Then, fold each wrapper in half. Starting at the center, pinch inward several times.
Place filled wontons on a clean plate and cover with a damp cloth or damp paper towel.
Repeat process until all wonton wrappers are filled.
Heat about 1 tbsp of vegetable oil in a large skillet over medium-high heat. Place potstickers flat side down in skillet. Cook for about 2 minutes, or until bottoms of the potstickers are browned. You will be able to fit about 24 potstickers in a 12 inch skillet. NOTE: If you do not want to use all potstickers right away, you can freeze the remaining 24 potstickers in a single layer. Once they have frozen for a few hours, you can place them in a large Ziplock bag.
Add 1/2 cup water to skillet and reduce heat to low so that the water is simmering (this assumes you are using about 24 potstickers in a 12 inch skillet). Place cover on skillet, but tilt it up so that steam can escape. Let steam until most of the water has evaporated, which will be about 5 to 7 minutes.
Remove potstickers from skillet. Immediately sprinkle with sesame seeds and diced chives. Serve with soy sauce for dipping.