Blanch ribs in a 4-quart pot of boiling water 4 minutes.
Drain and pat dry.
Whisk 1/2 teaspoon salt into cornstarch in a large bowl.
Add ribs and toss.
Heat 3 inches oil to 400°F in a 4- to 5-quart heavy pot, then fry ribs (in batches if necessary) 5 minutes per batch.
Transfer with a slotted spoon to a bowl.
Heat 2 tablespoons oil in a heavy medium saucepan over medium heat until it shimmers, then cook garlic, shallot, and ginger, stirring occasionally, until pale golden, about 2 minutes.
Add brown sugar and cook, stirring, until dissolved, about 1 minute.
Add wine and boil 1 minute.
Add ribs with broth, vinegar, and soy sauce and simmer, covered, stirring and turning ribs occasionally, until tender, about 1 hour.
Transfer ribs to a platter. Boil sauce, whisking, until thickened and emulsified, about 2 minutes; pour over ribs.