Preheat oven to 350°. Drain cherries, reserving 3/4 cup liquid from cans. Coarsely chop 1/2 cup cherries, and drain well, pressing between paper towels to squeeze out excess juice.
Prepare cake mix batter according to package directions; stir chopped cherries into batter.
Lightly grease 2 (6-cup) jumbo muffin pans with cooking spray. Spoon batter into 10 muffin cups, filling two-thirds full.
Bake at 350° for 17 to 19 minutes or until a wooden pick inserted in center comes out clean. Cool completely in pans.
Meanwhile, bring remaining cherries, sugar, and reserved cherry liquid to a boil in a saucepan over medium-high heat. Reduce heat to low, and simmer, stirring constantly, 1 minute. Stir together cornstarch and 2 Tbsp. water until combined. Quickly stir cornstarch mixture into cherry mixture, and cook, stirring often, 2 minutes or until mixture begins to thicken. Remove from heat, and cool 15 minutes.
Hollow out a 2 1/2-inch hole from the top of each muffin. Top each with about 2 Tbsp. cherry mixture.
Spoon whipped topping into a medium bowl. Stir in brandy, if desired, just before serving. Dollop mixture over cakes. Serve immediately, or chill 24 hours.
Note: We tested with Oregon Fruit Products Pitted Red Tart Cherries In Water.