Galette Dough

Ingredients

In a food processor, pulse the flours and salt. Add in the cold butter and process about 5 times until the butter becomes small pieces. Add the cold water and white wine vinegar. Pulse 3-5 more times until the dough begins to come together.
Poor the dough onto a piece of plastic wrap and combine into a disk. Double wrap the dough to ensure it is tightly wrapped in plastic and refrigerate for at least 3 hours before use. If freezing the dough, let it thaw before using.
When you are ready to use it, flour a clean work surface with all-purpose flour. Use a rolling pin to roll it out into a rough circle (about 14 inches). Transfer the circle to a parchment lined baking sheet and fill with your filling of choice (see recommendations here). Make sure to leave at least 3 inches of overhang to use as the edge. Fold the dough over the filling in small sections to seal your galette. If the dough is feeling soft put the whole thing in the fridge for 20 minutes before backing. Beat an egg in a small bowl and use a pastry brush to brush it onto the edge of the galette. If making a sweet galette sprinkle sugar on the egg washed edges.
Bake at 425 ºF (220 ºC) for 35 to 40 minutes until the crust is a deep golden brown. Depending on your filling you use, you may need to bake it longer. If the crust is browning to quickly cover it with tin foil. Let cool until the filling is set and then serve.