This is an open-faced peach pie baked on a covered grill in a cast-iron skillet. The topping is a nutty streusel. If your grill has a temperature gauge, set it for 400 degrees F and then turn down to 375 degrees F as noted in the directions. Anything around 375 degrees F will get the job done. If the streusel is browning too quickly, simply cover with foil. P.S.: Freestone peaches are peaches that come away easily from the pit, making them easy to slice. Ask the vendors at the farmers market if you can; it will make prep that much easier. To keep this rustic, I like to leave the skin on half the peaches, but it is up to you.
In a small bowl combine the pecans, sugar, flour, butter, and oats. Mix together with your fingertips to make a crumbly topping.
Preheat the grill to 400 degrees F. Coat a 9-inch cast-iron skillet with nonstick spray.
Roll out the dough on a floured surface to a 12-inch round. Transfer to a pie pan. Fold the edge under, and crimp decoratively.
Toss together the peaches, sugar, and cream in a mixing bowl; scrape into the crust. Top the peaches with the streusel
Place in a covered grill and adjust heat down to 375 degrees F. Bake until the filling bubbles and the topping is a light golden brown, about 55 minutes. Cool the pie at least 30 minutes on rack before serving. Can be made up to 6 hours ahead.