To make the crust, place gluten free all-purpose flour, oat flour, and salt in the bowl of a food processor. Pulse 4-5 times, just to mix the dry ingredients. Place the butter in the food processor bowl, and pulse 4-5 times again. Add the vinegar and 8 tablespoons of water, and pulse until it begins to come together (about 10 times). If needed, add more water, 1 tablespoon at a time, until the mixture just comes together.
Place the crust onto a well floured (using the gluten free all-purpose flour) surface, and roll to a rectangle that is about 12X16 inches. Place on a lightly greased, parchment-lined baking sheet, so that there is a bit of crust overhanging the edge. Trim the edges so they are flush with the baking sheet, reserving any excess dough for fun cutouts to place on top of the pie. Place the pie dough in the refrigerator while making the pie filling.
To make the Salted Caramel Apple Pie filling, toss together the apples and gluten free all-purpose flour in a large bowl and set aside.
Place granulated sugar and light brown sugar in a medium saucepan over medium heat. Gently stir the sugar, creating a well in the center. As the sugar begins to caramelize, gently stir a bit more sugar from the outside of the well into the center. Keep doing this, periodically, as the sugar caramelizes. This will take about 10 minutes. While the sugar is melting and caramelizing, heat the heavy cream and butter in the microwave.
Once the sugar has turned a dark amber color, reduce the heat to low and gently stir in the heavy cream and butter mixture, a little at a time. Slowly whisk in the lemon juice, vanilla extract, salt, cinnamon, ginger, nutmeg, and cloves. Toss the sugar mixture with the apples, until well combined. Set aside while making the streusel topping.
To make the streusel topping, mix together the gluten free all-purpose flour, oats, brown sugar, cinnamon, salt, and butter in a small bowl using your hands. Rub the mixture together until small, pea-sized pieces form. Set aside.
Place the filling over the crust, and spread evenly.. Top evenly with the streusel topping. Bake for 25-30 minutes, or until the crust is golden brown and the filling is beginning to bubble through the streusel topping.
Let cool for 2 hours before cutting.