Preheat oven to 350°F. Spray an 11 x 7-inch baking dish with cooking spray.
Combine brown sugar and corn starch in a small saucepan. Stir in syrup and lemon juice.
Cook over medium heat, stirring constantly until mixture boils. Boil for 1 minute; remove from heat and set aside.
Stir together sweet potatoes, apples and cranberries in prepared pan; top with glaze. Mix well. Cover with foil.
Bake for 30 minutes. Remove foil, stir and continue to bake for 15 to 25 minutes or until sweet potatoes are tender.