Roll dough to 1/8-inch thickness on work surface dusted with brown rice flour.
Cut dough into a 10-inch circle, and transfer to a baking sheet lined with parchment paper. Set aside.
Split vanilla bean lengthwise, and scrape out seeds.
Combine vanilla seeds, blueberries, and next 5 ingredients in a bowl.
Sprinkle almond flour in center of prepared dough, and spoon berry mixture on top, leaving a 2-inch border. Fold edges of dough over berry filling, pinching together to seal any cracks. Refrigerate 20 minutes.
Brush edges of galette with egg, and bake at 400 for 25 minutes or until filling bubbles and crust is golden brown.
