Preheat your oven to 400 degrees F. Line 2 baking sheets with parchment paper and set aside.
In a medium mixing bowl, beat together the cream cheese, ⅓ cup sugar, egg yolk, vanilla, lemon zest, and lemon juice with a hand mixer until smooth. Set aside.
Place a sheet of puff pastry on a clean work surface. Use a rolling pin to smooth out the pastry so there are no creases. Cut the pastry into quarters and place the dough pieces on one of the prepared baking sheets. Then take the corners or each piece and fold them into the center. Repeat with the remaining pastry.
Place 1 ½ tablespoons of the cheese filling in the center of each piece of dough.
Whisk together the egg and water. Brush the exposed pastry with egg wash. Sprinkle the remaining 2 teaspoons of sugar over each pastry.
Bake for 16-18 minutes until puffed the pastry is golden brown. Remove from the oven and place on a wire rack to cool for 10 minutes. The danishes will deflate while cooling.
Notes
You can taste the lemon in the filling. If you don’t want any lemon flavor, leave out the lemon juice and zest. They will still be delicious. However, lemon juice helps to counteract the richness of the cream cheese and I recommend using it.
You can skip the added sugar on top but I like that it gives a slight crunch and more sweetness to the pastry itself.