For the Wontons:
For the Chili Crunch Sauce:
Make the Filling: Heat a small skillet with a drop of oil. Add the garlic and ginger and sauté for 1 minute until fragrant. Toss in the shredded cabbage, carrots, spring onions, and bell pepper. Stir in the soy sauce, sugar, salt, and pepper. Cook for 3-4 minutes until the vegetables are softened but not mushy. Remove from heat and let cool.
Assemble Wontons: Place 1 teaspoon of the vegetable filling into the center of a wonton wrapper. Wet the edges of the wrapper with water, fold it into a triangle or gather the edges up into a purse/bowl shape, and press firmly to seal.
Make the Sauce: In a small saucepan, heat the sunflower oil over medium-low heat. Add the diced onion and garlic, cooking until lightly browned and crispy (about 5 minutes). Remove from the heat and carefully stir in the chili flakes, toasted sesame oil, tamari/soy sauce, and sugar.
Cook the Wontons: Bring a pot of water to a boil. Drop in the wontons and cook for 3-4 minutes until they float to the top. Remove with a slotted spoon.
Toss and Serve: Place the cooked wontons in a bowl, pour the prepared chili crunch sauce directly over them, and toss to coat.