Preheat oven to 400˚F. Line two baking sheets with parchement paper and set aside. 

In a large mixing bowl or stand mixer, combine the mascarpone cheese, two tablespoons of the sugar, vanilla extract, and almond extract. Stir well until the mixture is a whipped consistency. Taste and add more sugar if you like. Set aside.

Prepare the galette dough. Place the flour, salt, and three tablespoons of sugar in the bowl of a food processor. Pulse to combine. Add the cubed butter and pulse again until crumbly. Then, with the motor running, pour in the ice water. Check the consistency of the dough. If you squeeze a bit and it holds together, it's ready. If it is still really crumbly, add more ice water, just a teaspoon at a time. Transfer the dough onto a sheet of plastic wrap and wrap it up and press it into a ball. Lightly flatten it into a disk, then place in the fridge for at least 20 minutes. 

On a lightly floured surface, cut the dough into eight pieces. Roll each one into a 1/4-inch-thicl circle and place one the prepared baking sheets. Galettes are supposed to be rustic, so don't worry about imperfections. Spread a heaping tablespoon of the mascarpone filling onto each round, then top with the blood orange and navel orange slices, leaving an inch porder at the edge of each galette. Roughly fold the edges of the dough in towards the center, leaving the middle of the galette exposed. Brush the edges of the galettes with the beaten egg. Sprinkle with remaing sugar, then bake for 35-40 minutes, until the crust is golden. Allow to cool on a wire rack.