Sift the dry ingredients (flour, sugar, baking powder, and salt) into a mixing bowl.
Add very cold cubes of butter and rub the mixture between your hands until it forms a sand-like consistency.
Add the cream and the cream cheese and mix with your hands until the dough comes together.
Knead the galette dough with the palm of your hand for a minute, just until the dough becomes smooth.
Form the dough into a disk and wrap it in plastic food wrap before placing it into the fridge for a minimum of one hour or overnight.
Prepare the filling by mixing the berries sugar, and starch together in a bowl.
Roll the chilled, rested dough out into a rough circle on the baking paper or silicon mat you will be baking it on, then dust all over with the almond flour.
Place filling on top of the dough. Gently and tightly fold the edges in over the filling. Apply the egg wash.
Put the unbaked galette into the freezer for 10-15 minutes while pre-heating the oven to 200C / 392F.
Bake the blueberry galette for 30 minutes. Allow to cool before serving.