In a large mixing bowl beat 1/2 cup butter with an electric mixer on medium to high speed for 30 seconds. Add 1-1/4 cups brown sugar, baking soda, apple pie spice, and salt. Beat until well combined, scraping sides of bowl occasionally. Beat in egg until well combined. Add 1/2 cup apple juice; beat on low speed until combined (mixture will look curdled). Beat in as much of the flours as you can with the mixer; stir in any remaining flour. Fold in apple.