This Chinese restaurant classic is easily made without cornstarch with a few tweaks. Notably, simmering store-bought chicken stock with collagen-rich chicken wings and fortifying with a bit of powdered gelatin, this is an easy soup that leaves nothing to be desired.
Add 250ml (1 cup) chicken stock to a large dish or measuring jug. At a height, sprinkle the gelatin over the stock, ensuring it's evenly distributed. Set aside until needed.
Add 1 tbsp of neutral oil to a medium saucepan and set over medium-high heat. Once shimmering, add the chicken wings and cook on one side until golden, about 3 minutes, before flipping and searing on the other side, a further 2-3 minutes. Pour over the remaining 750ml (3 cups) of chicken stock and add the scallion whites and shiitake mushrooms. Bring to a simmer and allow to simmer for 30 minutes.
Strain the solids from the broth and return to the pot. Add the gelatin-fortified stock along with the soy sauce and vinegar. Return to the stovetop and heat to just below a simmer.
Turn off the heat and slowly stream in the beaten egg through the tines of a fork. Taste to adjust for seasoning, adding salt if needed. Serve, topping with scallion greens.
Notes
For best results, use unsalted stock so you can control the seasoning of the final dish.
Make Ahead
Stored in an airtight container in the fridge, the soup will keep for up to 3 days. The gelatin will likely set when cooled, do not be alarmed. Reheat gently on the stove until just below simmering. Do not freeze.