Begin by making the cinnamon simple syrup. In a small pan on the stove, combine 1 ½ cups sugar, 1 ½ cups water, and ¼ teaspoon of cinnamon. Over medium heat bring to a boil. When the sugar is dissolved, remove from heat. Add three tablespoons of butter and stir to melt.
For the dumplings, combine the two pie crusts into one big dough ball and roll out into a 12x18 inch rectangle. Then cut into six squares.
To each square add sliced and peeled apples. Use a half an apple to a whole apple per square depending on the size of your apples. Put a half a tablespoon of butter on the apple and then sprinkle with cinnamon and sugar. Repeat.
Then wet the edges of the crust and bring around the apples to form the dumplings. Place the dumplings in a 7X11 baking dish.
When apple dumplings are all made, pour the syrup over the top of the dumplings.
Bake at 375° for 35 minutes. Continue to spoon the syrup over the dumplings as they bake.