Heat oven to 375 degrees F. Spray an 8-inch square baking pan with nonstick cooking spray.
In a large bowl, whisk together flour, cornmeal, sugar, baking powder and salt. In a medium bowl, whisk together milk, butter and egg.
Pour the milk mixture into the flour mixture and stir until evenly moistened. Fold in the Mexicorn. Spoon batter into prepared baking pan and spread evenly.
Bake at 375 degrees F for 30 minutes or until top of corn- bread is golden. Allow to cool in pan on wire rack 10 minutes.
To serve, gently remove from pan; cut into 12 squares.