Heat the avocado oil in a wok over medium heat. Add shallots and garlic, cooking gently until golden and fragrant, 8-10 minutes.
Add the dried shrimp and scallops, stirring frequently, and cook 15-20 minutes over low heat until deeply fragrant and slightly crisp at the edges.
Stir in the chili flakes, soy sauce, Shaoxing wine, and allulose. Simmer gently 5-10 minutes more, stirring often to prevent sticking.
Cool completely before transferring to a jar, making sure the sauce is fully covered by oil. Keeps refrigerated for up to a month.
Notes
Makes about 1 1/2 cups. Keep the heat low throughout - this sauce is built on slow rendering, not searing, and rushing it burns the aromatics before the seafood dries out properly.