Fill a large pot with water and bring it to a rolling boil. Prepare the chicken by combining it with cornstarch, one teaspoon of neutral oil, and water. Mix well to coat.

Add the prepared chicken to the boiling water, gently stirring for about 45 seconds or until the pieces turn opaque. Remove with a slotted spoon and set aside. Repeat this process with the shrimp, cooking for 45 seconds to one minute, depending on their size. Be cautious not to overcook. Transfer the shrimp to a separate plate.

Carefully drop the frozen wontons into the boiling water and allow them to cook for approximately six minutes.

In a wok set over medium-high heat, add the remaining tablespoon of neutral oil. Introduce the minced garlic, sliced carrots, and mushrooms, sautéing for about two minutes until the carrots become slightly tender and the mushrooms develop a rich, golden hue.

Incorporate the bok choy stems and continue stir-frying for an additional minute. Pour in the chicken stock and bring the mixture to a gentle simmer. Once the broth is heated, add the char siu (or ham), pre-cooked chicken, and shrimp. Allow the soup to return to a simmer.

By this time, the wontons should be fully cooked. Remove them from the boiling water using a strainer and distribute them evenly among four serving bowls.

Once the soup has reached a gentle simmer, mix in the bok choy leaves along with the salt, white pepper, and sesame oil. Stir thoroughly, then taste and adjust the seasoning if necessary. Ladle the hot broth and its ingredients over the wontons, ensuring an even distribution. Serve immediately and enjoy.