FOR THE DANISH
1 sheet (roughly 8.7-oz) puff pastry, thawed if frozen
6 oz. cream cheese, softened
3 tbsp. powdered sugar
1 large egg, divided
1/2 tsp. lemon zest
1/4 tsp. kosher salt
Vegetable oil, for greasing
1/4 c. raspberry jam
2 tsp. granulated sugar
FOR THE GLAZE (OPTIONAL)
3/4 c. powdered sugar
2 -3 tsp. milk
Preheat oven to 400° and place a medium baking sheet in to preheat. In a large bowl using a hand mixer or whisk, beat cream cheese until smooth, 1 to 2 minutes. Add powdered sugar, egg yolk, lemon zest, and salt and beat until fully combined.
Line a large cutting board with foil, then rub a couple teaspoons of vegetable oil onto foil to coat. Place puff pastry on foil, then fold each corner in 2” in to make an octagon. Transfer cream cheese mixture to the center of the pastry and smooth into an even layer, leaving about 1” pastry uncovered around the edges.
Spoon jam into the center of the cream cheese mixture and smooth into an even layer, leaving a 1” border of visible cream cheese mixture. Beat reserved egg white with 1 teaspoon water and brush all over exposed pastry dough, then sprinkle with granulated sugar. Place cutting board in freezer for 10 minutes.
When ready to bake, carefully remove hot baking sheet from oven and place somewhere stable and heat-proof. Remove cutting board from refrigerator and hold over hot baking sheet. Gently slide foil (and Danish) off cutting board onto baking sheet. Bake until pastry is golden, 20 to 25 minutes, turning halfway through. Let cool at least 45 minutes before serving.
Make glaze: In a small bowl, whisk together powdered sugar and milk until smooth, then drizzle over cooled Danish.