In a mixing bowl, add in the flour and sugar. Stir to combine.
Add the cold butter into the flour. Cut the butter into the flour until the butter forms small pea sized pieces.
Add in the cold water started at 6 tablespoons. If the pie dough doesn't stick together, add the remaining 1 to 2 tablespoons of water.
Dust a clean surface with flour. Turn out the dough and cover the rolling pin with flour. Roll the pie dough out to fit an 8 inch pie plate.
Run the spatula under the pie crust to loosen it from the counter.
Fold in half and move to the pie plate.
Cut off the edges and crimp them. Place some vent holes in the crust with a fork. I would 3 - 4 pricks of the fork would do the trick.
Weigh down the piece crust with a piece of parchment paper and some dried beans. The beans won't be any good for eating after they are used for par barking. You can use pie weights if you have them.
Place in the oven to bake for about for about 15 - 20 minutes. Just until the crust begins to brown up. Remove from the oven and begin making the filling.
Reduce oven temperature to 350 degrees.
Filling
In a large mixing bowl, add in the melted butter and peanut butter. Stir until incorporated.
Add in the brown sugar and stir until incorporated. Try to prevent any lumps of brown sugar. I used the back of my spatula to crush any lumps that I found.
Add in the corn syrup and stir to combine.
Add in the beaten eggs and stir until the eggs disappear into the other wet ingredients.
Add the old fashioned oats on top of the par baked pie crust.
Pour the filling on top of the oats. I sprinkled a few extra oats on top to let people know they were in there.
Place in the 350 degree preheated oven and bake for 45 - 50 minutes until the center is still jiggly but the outer edges are not.
Turn off the oven and let the pie stay in there for another hour or so. The leftover heat will continue to bake the pie some.
Let cool and refrigerate for at least 3 hours, but preferably chill overnight.