1. In a bowl of a stand mixer, place together flour, sugar, xanthan gum and salt.
2. Add butter to the flour mixture.
3. Put the electric mixer, on slow speed and cut the butter into cubes until it forms about 1-centimeter pieces.
4. Put the mixer on at slow speed, add egg and water to the flour mixture.
5. While still mixing, drizzle ice water, just a few tablespoons at a time, until all the flour is damp.
6. Raise the speed and mix for 2 minutes or until the flour comes together.
7. Remove the dough from the mixer bowl.
8. On a clean working table, knead the dough with hand, just to bring it together.
9. Using a dough cutter, cut the dough into parts, wrap with plastic film and chill in refrigerator for about 2 hour.
10. After two hours, remove the dough from refrigerator.
11. Roll each part of dough and use as needed.