Preheat oven to 350 degrees. Put the pie shell in a 9 inch pan. Spread the melted butter on the crust inside the pan. Then sprinkle on 1 tsp. each of cinnamon and sugar.
For the syrup, simply mix in the butter, cinnamon, brown sugar, water, and corn syrup in a small saucepan. Bring to a boil and let it boil gently for 2 minutes, stirring gently until the sugar is dissolved. Remove the pan from the heat and add 1 teaspoon vanilla to the syrup.
For the batter, mix the butter until light and fluffy in your stand mixer. Add in the the sugar, powdered sugar, baking powder, salt, cream of tartar, egg, vanilla, milk, and flour as listed.
Mix just until combined. Spread evenly on your pie crust.
Slowly pour on the syrup over the dough, and cover the edges of the pie in foil. Bake at 350 degrees for 25 minutes. Then take the foil off, and bake for the remaining 20 minutes. Serve with ice cream or just enjoy it as is!