Stir together flour and cornstarch in a shallow dish.
Sprinkle turkey with salt and pepper. Dredge turkey in flour mixture, shaking off excess.
Cook turkey in 2 Tbsp. hot oil in a large skillet over medium-high heat 2 to 3 minutes on each side or until golden.
Drain on paper towels.
Heat remaining 2 Tbsp. oil in skillet; add sage. Cook, stirring often, 2 to 3 minutes or until crisp and fragrant.
Remove with a slotted spoon; drain on paper towels.
Add shallots, and saut 2 to 3 minutes or until tender.
Add wine, and cook 3 to 4 minutes or until mixture is reduced by half, stirring to loosen brown bits from bottom of skillet.
Add broth, next 2 ingredients, and turkey. Bring to a boil over medium-high heat; reduce heat to medium-low, and simmer 10 minutes or until mixture is thickened.