Heat the oil in a large saucepan or wok over high heat. Cook the garlic and ginger until fragrant and lightly browned. Stir in the shrimp, and stir fry until cooked, then remove and set aside. Pour in the chicken stock and bring to a boil. Reduce heat to
medium, add the tofu and peas, season with salt and pepper, then return to a simmer. Mix the cornstarch with a little water to form a thin paste. Stir the cornstarch into the soup and continue to simmer until clear and thickened, about 1 minute. Stir the shrimp
back into the soup and serve.