Optional step: Make some shrimp stock. In a small saucepan, add the heads and shells from the shrimp used in this recipe, and cover with about a cup of water. Bring to a boil and simmer, 10 to 15 minutes. Do not simmer any longer than 25 minutes as the stock might get bitter. Let cool for a bit and pour into your blender jug. Blitz into a fine puree, and strain. Set aside until ready to use.
Prepare the sauce. In a medium-sized bowl, add the light soy sauce, 3 tablespoons sweet soy sauce, chicken powder, ground white pepper, and all-in-one seasoning powder. Stir to combine and set aside.
In a large wok over medium-high heat, heat the oil.
Add the garlic and cook, stirring, until slightly golden.
Add the cili boh and cook, stirring, until all the liquid has been cooked off.
Flash fry the chicken, stirring constantly, until just cooked.
Stir in the oyster sauce, fishballs, and shrimp.
Pour the sauce mixture, and stir until all the ingredients are well-coated.
Add the stalks of the choy sum, carrots, and sesame oil. Cook, stirring, until slightly softened, 2 minutes.
Add the soaked rice noodles. Toss the noodles to completely coat in the sauce and thoroughly combine all the ingredients.
Ladle some of the shrimp stock or water onto the noodles, and keep stirring until the liquid evaporates. This process is to soften the noodles. Repeat this step a few more times until the noodles are soft.
Add the choy sum leaves and stir, until wilted. The noodles are done when they start breaking into smaller strands.
Add the cooking caramel, about a tablespoon at a time, until the noodles have the desired dark brown color.
Make the egg topping. In a small bowl, add the egg and seasoning powder, and stir to thoroughly combine.
In a wide skillet over medium heat, heat some oil. When the skillet is properly hot, add the egg mixture.
When the bottom side is lightly browned, flip and brown the other side.
Transfer the thin omelet to a cutting board and tightly roll.
Chop the omelete into tiny shreds.
Transfer the noodles to a large serving platter. Top with the green onions.
Spread the egg strips all over the noodles.
Garnish with the chili slices. Serve immediately.