Preheat oven to 400ᵒF. Line a baking sheet with parchment paper. Beat egg with 1 tablespoon water and set aside.
Lightly flour a smooth work surface and roll out the crust so that it is a little less than ¼” in thickness. Use a 3 inch round cutter to cut out as many circles as you can. Gather the leftover crust and roll out again, aiming to get 20 circles total.
In a bowl, toss together blueberries, 1 tablespoon Splenda Sugar Blend, corn starch, lemon juice and zest. Gently mash a bit with the back of a fork. Don’t over-mash.
Spoon the filling into the center of half of the rounds, leaving a little border around the edge. Brush egg wash along the edges, and then place another round on top. Press down with a fork around the sides to crimp the edges of the hand pie. Put three small slits in the top of each with a knife, so that steam can escape as the pie bakes. Brush a little more of the egg wash over the top crust. Sprinkle the rest of the Splenda Sugar Blend on top of the hand pies.
Bake for 10-12 minutes, until crust is lightly browned on top and around the edges. Blueberry juice might bubble over just a bit. Remove and let cool completely. Serve immediately and enjoy!