First:

Set out cream cheese to come to room temperature, in a medium-large mixing bowl.

Crust:

Combine the flour, sugar, and salt in a large bowl. Cut the cold butter into chunks and add it to the flour and salt. Use a pastry cutter or your hands to work the butter into the flour until the flour looks like damp sand with some pea-sized pieces of butter.

Begin adding ice water, one tablespoon at a time, until a dough forms and no dry flour remains on the bottom of the bowl.

Shape the dough into a flattened disc, wrap it in plastic, and refrigerate for one hour or until solid.

Lemon Blueberry Filling:

While the dough is refrigerating, combine the blueberries, sugar, cornstarch, lemon zest, and 1 Tbsp lemon juice. Stir them together well and set the mixture aside.

Cream Cheese Filling:

In a separate bowl, combine the cream cheese, sugar, egg yolk, and 1 tsp lemon juice until it forms a smooth mixture.

After the dough's been in the fridge for 1 hour:

Preheat the oven to 400ºF.

Lightly flour a clean work surface.

Line a large baking sheet with parchment. (use our biggest baking sheets for this)

Roll out the dough: Take the dough out of the refrigerator and roll it into a 14"-16" circle. The dough may seem a little stiff at first, but it will become more pliable as it warms. Make sure to keep your work surface dusted with flour as you roll to keep the dough from sticking.

Transfer the rolled dough onto the parchment (you can either roll or fold the dough to transfer without ripping).

Add the cream cheese: Spread the cream cheese mixture over the center of the circle, leaving about 2" bare around the outside edge. I like to leave a higher "lip" on the outer edge of the cream cheese to help hold in the berries and their juice.

Add the blueberries: Stir the blueberries one last time and pour them over the cream cheese, including all of the juice from the bowl.

Fold up the galette: Begin folding up the sides of the dough over the cream cheese and berries, leaving the center open.

Brush the crust: Whisk the egg white with a fork, using a drop or two of water to make it more fluid, if needed. Brush the egg white over the surface of the galette dough.

Bake the galette for 30 minutes, or until the crust is golden brown.

Let it sit for 10 minutes before slicing into 4 pieces and serving.