Preparing the Puff Pastry:

1. Thaw Puff Pastry: Let the puff pastry sheets sit at room temperature for 30 minutes to 1 hour until softened. Alternatively, wrap each sheet in paper towels and microwave for 15 seconds on each side until easily unfolded.
2. Preheat Oven: Set to 375°F.

Making the Cream Cheese Filling:

1. Beat Ingredients: In a large bowl, beat cream cheese and sugar with a mixer on medium speed for 2 minutes.
2. Add Yolk and Flavorings: Add the egg yolk, lemon juice, and vanilla extract. Beat until well combined.

Assembling the Pastries:

1. Cut Pastry: Unfold each puff pastry sheet and cut each into 6 rectangles.
2. Prepare Baking Sheet: Place the rectangles on a baking sheet lined with parchment paper or a silicone mat.
3. Score Pastry: Score a smaller rectangle in the center of each piece without cutting all the way through.
4. Add Filling: Spoon a couple of tablespoons of the cream cheese filling into the center of each pastry.
5. Top: Add berries, a teaspoon of jam, or leave just the cream cheese filling.

Preparing the Egg Wash:

1. Whisk Egg: Whisk the egg to create the egg wash.
2. Brush and Sugar: Brush the edges of each pastry with the egg wash and sprinkle with coarse sugar.

Baking the Pastries:

1. Bake: Place in the preheated oven and bake for 15-20 minutes until the pastry is puffed and golden brown.
2. Cool: Allow the pastries to cool for about 10-15 minutes.

Making the Glaze:

1. Mix Glaze: Combine powdered sugar and milk until the glaze is thick but runny. Adjust consistency by adding more powdered sugar if too runny or more milk if too thick.

Serving:

1. Drizzle Glaze: Drizzle the glaze over the pastries using a spoon. Alternatively, sprinkle powdered sugar on top.
2. Enjoy: Serve immediately or store in the fridge.