Start by making the homemade Danish pastry a day in advance for the best results. Combine flour, sugar, and salt in a large bowl, then incorporate butter until the mixture resembles coarse crumbs. Gradually add chilled water, mixing just until combined. Form the dough into a rectangle, wrap it in plastic, and refrigerate for at least 8 hours to achieve a flaky texture.

Once the dough has rested, preheat your oven to 400°F (200°C). Lightly flour your work surface and roll the chilled dough into a large rectangle, about ¼ inch thick. Trim the edges for a clean cut, then cut the dough into squares, roughly 4x4 inches.

Take each square of dough and gently press down in the center to create a well for the filling. Arrange the shaped squares on a parchment-lined baking sheet.

In a mixing bowl, combine softened cream cheese with granulated sugar, milk, and lemon zest. Blend until smooth and creamy.

Spoon about a tablespoon of strawberry jam into each dent of the shaped pastry squares. Add a dollop of the cream cheese mixture on top of the jam. Scatter fresh strawberry pieces over the cream cheese.

Brush the edges of each pastry with egg yolk to achieve a golden color once baked. Sprinkle demerara sugar generously over the edges.

Place the baking sheet in the oven and bake for about 20 minutes, watching for a golden-brown color and flaky layers.

Once done, let them cool on a wire rack for about 5-10 minutes. Serve warm, optionally dusted with powdered sugar.