Rinse blackberries under cool running water and let drain.
Spread berries on a paper towel lined sheet pan and let dry.
Prepare two batches of our Basic Pie Crust recipe.
Place sugar in a medium sauce pot.
Add butter.
Mix cornstarch in one cup of cool water. Stir until dissolved.
Add cornstarch and water to the sauce pot.
Stirring constantly, bring to a low boil over Medium heat.
Let cook on low boil for one minute. Remove from heat.
Add vanilla flavoring. Stir well. Set aside.
Roll dough for bottom crust and top crust.
Place dough in bottom of 9 x 13 inch pan that has been lightly buttered.
Add the berries.
Pour syrup over the berries.
Add the top crust.
Bake at 400F degrees for 30 to 40 minutes until top crust is lightly browned.
Remove when done. Place on wire rack to cool slightly before serving.
Enjoy!