Remove pits from 3 pounds cherries. The easiest way is to use a cherry pitter for this.
Cut the cherries in half. You don't have to cut all of them, but the majority.
In a medium sauce pan, cook the cherries, sugar and the extract for five minutes while stirring.
Mix the cornstarch and the lemon in a small bowl, then add to the cherry multure while still cooking over medium heat. Continue to stir.
Cook for anther four minutes until thick.
Let the mixture cool to room temp while you make the crust.
Buttery Pie Crust
In a large bowl combine flour and salt and sugar.
Cut 2 sticks butter into small chunks and add to the flour mixture. With your hands or a pastry cutter, blend until butter chunks are the size of peas.
Add ice water and mix dough with hands until combined. The dough should hold a loose ball and be more on the dry side. It should look rough.
Roll the dough out and fit it into the pie dish. You can refrigerate freeze it for 30 minutes in the pie dish, which I recommend doing.
Assembling the Pie and Hearts
Remove a little less than half the pie crust and set aside.
Roll the remaining dough out on parchment paper to about 12" circle to fit in a 9" pie dish (it doesn't need to be perfect!) then flip it over into a pie dish.
Press it down in the center and up to the sides. Create a crust around the edge of the pie, using your hands to mold it.
If you need a little extra dough to create more crust or an area that needs more, just take it from the preserved dough.
Once the dough is pressed nicely in the pan with a pretty crust, place it in the freezer and let it sit there while you make the hearts.
Roll out the remaining dough (about 1/4" thick) on parchment paper and using a 1" heart cookie cutter, cut out about 75 little hearts... or as many as you can with the dough.
Keep rolling the dough out and cutting again. Then once you have all the hearts you can start assembling the pie!
Pour the cherry mixture into the cold pie crust.
Start around the outer edge and add the hearts. Continue until you get to the center of the pie. Leave a little room in the center to see the cherry pie filling.
Whisk an egg with a fork and give the crust and hearts and egg wash. Really get all of the top and cracks good so it turns golden brown. You can sprinkle a little sugar on top too!
Bake in a 375 degree oven for 20 -25 minutes until the crust is golden brown. Let it cool about 30 minutes before serving. Enjoy!