Roll out pie crust and place in 9-inch deep dish pie plate.
Prick small holes in the bottom of the crust with a fork.
Line with parchment paper or aluminum foil. Fill with pie weights or dry beans.
Bake for 10 minutes, then remove from oven and set aside.
Drop oven temperature to 350°F.
Filling
Remove inner flesh from dragon fruit.
Puree the fruit either in a blender or with an immersion blender. Blend until just barely smooth, but not so much that you obliterate the seeds.
Place in a medium saucepan with ½ cup of sugar and cook over medium low heat until it starts to simmer.
Stir mixture frequently while it simmers for about 5 minutes.
Make a slurry of 1 Tablespoon of water and the cornstarch. Stir into simmering dragon fruit mixture and cook until thickened. Remove from heat to cool.
Meanwhile, beat cream cheese in a mixing bowl until it is smooth and creamy.
Add egg, vanilla, lemon extract and remaining 1/2 cup sugar and beat until well mixed.
Stir in dragon fruit mixture, then spoon filling into pie crust.
Bake at 350°F for 45-50 minutes. The pie should be mostly set with just a slight wobble in the center.
Cool at room temperature for about an hour and then chill for at least 2 hours before serving.