In a small saucepan combine apple pie filling and water. Heat to a simmer over medium high heat, stirring occasionally. Remove from heat and strain through a fine mesh sieve to remove apple pieces. Chill until ready to use.
To make a cocktail:
Fill a cocktail shaker with ice. Pour in apple pie syrup, bourbon and apple brandy. Shake until well chilled and strain into two ice filled glasses. Top each glass with ginger ale or sparkling water to fill, if desired. Stir gently to combine.
Notes
If your apple pie has a lot of apples in it (like a homemade pie typically does), you may need to add an additional 1/2 cup of water and 1/4 cup of sugar to make the syrup.