To make the pie dough, combine the flour and salt in a small food processor. Cut the butter into small pieces and add it to the processor. Pulse several times, just until the mixture resembles course sand and the butter is the size of small peas. If you do not have a food processor, cut your butter into the flour mixture with a pastry knife or two knives, working quickly so that the dough remains cold. Add the ice-cold water one tablespoon at a time and mix with fork until the dough just begins to come together as you form it into a ball with your hands. Again, do not over work or over handle the dough. The flakiest of pie and galette doughs have been handled the least (it's the same concept as when shaping biscuits). 

Using your hands, form a flat disc (wet your hands if need to get the final formation of the dough) and wrap the the disc in plastic. Allow it to rest and refrigerate for at least thirty minutes and up to two hours.

After the dough has rested, preheat your oven to 425ºf. Mix together the maple syrup, flour and cinnamon and stir in the blueberries and lemon juice.

To prepare the galette, line a large baking sheet with parchment paper. Grease and dust with flour.  Remove your dough from the fridge and using a very clean work surface or large cutting board, dust the entire surface with more flour. Remove the dough from the plastic and dust both sides with more flour. Working quickly but gently roll your dough into an eight to ten inch disc and place it onto the prepared baking sheet. If you're dough has become too soft or warm, return it to your fridge or freezer for five to ten minutes. 

Pour the combined blueberries into the prepared galette dough, leaving about a one and a half inch border of dough. Using just the tips of your fingers, pinch the dough together working around the entire galette,  creating eight or more seams to ensure the blueberries are secure. Return your galette to the freezer or fridge (trust me, you want to really make sure the dough is quite chilled - this creates the flakey crust we all dream of) and beat an egg vigorously until the egg whites and egg yolks are fully incorporated. Using a pastry brush, thinly coat the outer surface of the galette dough with egg wash. Sprinkle the top of the blueberries with the remaining tablespoon of butter and a tablespoon of turbinado sugar, if desired. 

Insert your beautifully prepared galette into the middle rack of your oven and bake at 425ºF for fifteen minutes. Reduce heat to 375ºF and continue to bake for twenty-five to thirty minutes, or until the dough is browned nicely and the blueberries are forming bubbles.

Remove from the oven, let cool for fifteen minutes and serve with fresh whipped cream (or local ice cream) and totally enjoy!