Preheat your oven to 400 degrees F (200 degrees C). Line two baking sheets with parchment paper.
Unfold the thawed puff pastry sheets onto a lightly floured surface. Cut each sheet into 6 equal squares, resulting in 12 squares total.
In a medium bowl, beat the softened cream cheese, granulated sugar, egg yolk, and vanilla extract until smooth. This is your cream cheese filling.
Place one pastry square on the prepared baking sheet. Using a small knife, lightly score a border about 1/2 inch from the edge of the square, being careful not to cut all the way through.
Spread about 1 tablespoon of the cream cheese filling inside the scored border of each pastry square.
Arrange a few strawberry slices on top of the cream cheese filling on each pastry.
Brush the edges (the border) of the pastry lightly with milk.
Bake for 15 to 18 minutes, or until the pastry is golden brown and puffed.
While the danishes cool slightly, prepare the glaze. Whisk together the powdered sugar and water until smooth.
Drizzle the glaze over the warm danishes. Warm the strawberry preserves slightly in the microwave for about 15 seconds, then spoon a small amount over the fresh strawberries on each danish.
Serve warm or at room temperature.
Notes
If you prefer a thicker glaze, use less water when mixing the powdered sugar.
For extra flakiness, chill the pastry squares for 10 minutes before baking.
You can substitute fresh strawberries with mixed berries if desired.