Position a rack in the cetner of the oven. Preheat the oven to 400°F and line two baking sheets with parchment paper.
In a medium mixing bowl, beat together the cream cheese, powdered sugar, egg yolk, lemon juice, and lemon zest until well combined and smooth with an electric mixer on medium speed. 8 ounces cream cheese ¼ cup (28 g) powdered sugar 1 egg yolk 2 teaspoons lemon juice Zest from 1 lemon
For the crumble topping, in a small mixing bowl, combine the flour and brown sugar. Cut in the butter until it looks like coarse breadcrumbs. I rub the butter into the flour/sugar mixture between my fingers, breaking it down into smaller pieces. Once combined and crumbly, stir in the almonds and oats. ¼ cup (60 g) all-purpose flour 2 Tablespoons unsalted butter 2 Tablespoons light brown sugar ¼ cup (21 g) sliced almonds ¼ cup (25 g) oats
Carefully unfold the thawed, but chilled, puff pastry. Different brands of puff pastry come in different dimensions. Gently roll the sheet into an 8-by-12-inch rectangle. Cut the rectangle down the middle and into thirds so you have 6 squares that measure 4 by 4 inches. If the sheet measures 10 by 15 inches, you can either cut it down to 8 by 12 or leave it as is and have a little larger Danish. The goal is to have a square shape so when the corners are folded in, they meet in the center. I also tested this with Pepperidge farm puff pastry sheets which measured 9 inches by 9 inches - so in this case you can roll out the pastry to 9 inches to 13 inches - or you can also cut into 6 rectangles and skip the folding. 1 package (2 sheets) Frozen Puff Pastry
Fold in each corner towards the center and press down in the middle.
Spoon about 1 ½ T of cream cheese mixture in the center of each pastry. Top with 5 blueberries. At this point if your pastry has warmed up a bit, you can always chill in the freezer for 10-15 minutes before egg washing and baking. 1 ½ cups fresh blueberries
For the egg wash, in a small bowl, whisk together the egg and water.
Using a pastry brush, brush edges with egg wash and sprinkle the crumble topping over the top. 1 egg mixed with 1 Tablespoon flour
Bake for 16-20 minutes, or until light golden in color. Remove from the oven and top with a few fresh blueberries as soon as the pan comes out of the oven. Let the Danishes cool while you make the glaze.
For the lemon glaze, place powdered sugar in a small bowl. Whisk in lemon juice and stir until smooth. With a spoon, drizzle glaze over Danishes and enjoy! 1 cup (113 g) Powdered Sugar 1-2 Tablespoons Lemon juice