Combine the aromatics in a small dish; cover until ready to use.
About 15 minutes before serving, bring 4 cups of water to a steaming near simmer. Add the shrimp, stir to separate, and cook until the outside turns 60% opaque and pink, about 20 seconds. Drain and set aside. The shrimp will be raw in the center.
Heat a wok or large heavy skillet over high heat until hot enough to evaporate a bead of water on contact. Add 2 tablespoons of the oil and swirl to glaze pan. When the oil is hot enough to sizzle a scallion ring on contact, reduce the heat to moderate and add the aromatics. Stir gently until fully fragrant, 20 to 30 seconds, adjusting the heat so they foam without browning.
Add the ground pork, stir-frying and separating the meat till it is fully brown. Add the shrimp and stir-fry for about a minute. Stir in the sherry, chicken stock, and sugar, and let the liquids come to a simmer.
Holding the container with the beaten egg over the wok, drizzle the egg slowly into the simmering liquid, stirring gently with a fork.
Stir the cornstarch mixture into the wok, stirring till thickened.
Garnish with scallion pieces.