Directions

1. Combine flour, sugar, and salt in a food processor. Pulse to combine.
2. Lay a large piece of plastic wrap near the food processor to use shortly.
3. Cut the cold butter into small pieces, about 1/2" cubes. Add the food processor and pulse until a coarse, crumb-like texture forms.
4. Add sour cream, and pulse continuously until a dough ball forms, about 1 minute. Carefully remove the blade from the food processor, then remove the dough ball. Lay the dough ball onto the plastic wrap, and gently form into a disc-shape about 1/2" thick. Wrap in plastic wrap, and refrigerate for 30 minutes.
5. Lightly flour a clean surface. After 30 minutes, remove the dough from the refrigerator and place it on the floured surface. Allow it to warm up slightly, about 4-5 minutes. Roll out to a circle about 12" in diameter. Transfer to a 9" pie dish and carefully trim the edges.