How to Make It
Prepare the Dough: Stir together flour and salt in a large bowl. Add butter, and toss to coat each piece completely with flour. Use a pastry blender or 2 knives to cut in butter until mixture resembles coarse crumbs. Stir together sour cream, water, and lemon juice in a small bowl until combined, and drizzle over flour mixture; stir into mixture with a fork until fully moistened. Pat into a disc and cut in half. Wrap each disc in plastic wrap, and refrigerate until chilled, about 30 minutes.
Prepare the Pumpkin-Chai Filling: Stir together all ingredients in a medium bowl until combined. Set aside.
Prepare the Pumpkin-Aged Cheddar Filling: Stir together all ingredients in a separate medium bowl until combined. Set aside.
Working with 1 disc of dough at a time, place on a lightly floured surface and sprinkle with flour. Roll to 1/8-inch thickness. Cut into 12 (3-inch) circles; roll each into a 4-inch circle (about 1/16-inch thickness). Spoon about 1 tablespoon filling of choice into center of each dough circle. Use your fingers to wet edges with water, and fold circle in half over filling, pressing edges to seal. Place on a baking sheet lined with parchment paper. Repeat with remaining dough circles. Re-roll dough scraps once; repeat process of cutting into circles and filling. Refrigerate until chilled, about 30 minutes. Repeat with remaining dough disc and filling of choice.
Preheat oven to 375°F. Remove pasties from refrigerator, and crimp sealed edges with a fork. Cut 3 small slits into pasty to create a vent (feel free to make a lightning bolt!). Beat together egg and 1 tablespoon water. Brush pasties with egg wash; bake in preheated oven until golden brown and puffy, about 20 minutes. Let cool about 5 minutes before serving.