Place the softened cream cheese in a medium bowl and beat with a fork until smooth. Add the finely chopped crab meat, minced green onion, soy sauce, Worcestershire sauce, sugar, garlic powder, and white pepper. Mix thoroughly until evenly combined and smooth. Taste and adjust seasoning (a few more drops of soy sauce or a pinch more sugar) if desired.

Prepare wrappers

Lay one wonton wrapper on a clean, dry surface. Keep remaining wrappers covered with a damp towel to prevent drying out. Spoon about 1 tablespoon of the crab-cream cheese mixture into the center of each wrapper. (For 4 pieces, you will use approximately 4 tablespoons total.)

Seal and shape

Dip your fingertip into the cold water and lightly moisten the edges of the wonton wrapper. Fold a corner over to form a triangle (if using square wrappers) or fold the wrapper in half (if using round) to make a half-moon, pressing out any air. Then bring the two outer corners together and press to seal, creating a purse or traditional rangoon shape. Ensure edges are sealed tightly to prevent filling leakage. Repeat for all 4 wrappers.

Heat oil

Pour vegetable oil into a small saucepan or deep skillet to a depth of about 1 to 1.5 inches (approximately 1 cup). Heat oil over medium-high heat until it reaches 350°F (175°C) or until a small piece of wrapper sizzles and browns within 10–15 seconds. If you don't have a thermometer, test carefully with the wrapper piece.

Fry rangoons

Carefully add 2 rangoons to the hot oil (do not overcrowd; fry in batches if necessary). Fry for 1.5–2 minutes, turning once, until golden brown and crisp. Use a slotted spoon to transfer rangoons to a plate lined with paper towels to drain. Fry the remaining 2 rangoons the same way.

Finish and garnish

Let rangoons rest 1–2 minutes to cool slightly. Sprinkle with sesame seeds and a little chopped cilantro or chives if desired. Serve immediately while hot and crisp with the dipping sauce on the side.

Dipping Sauce

Combine sweet chili or plum sauce with soy sauce and rice vinegar in a small bowl. Stir until smooth. Taste and adjust balance by adding more vinegar for tang, soy for salt, or sauce for sweetness. Transfer to a small dipping dish and serve alongside hot rangoons.