Place the butter and cream cheese in a large mixing bowl and beat until smooth, about 1 minute.
Add the sugar and cream together until fluffy, about 3 minutes.
Mix in the flour and salt just until combined, divide the dough into 4 equal portions, and refrigerate for 1 hour.
On a lightly floured surface, roll out each portion of dough to a circle about 1/8-inch thick.
Spread each circle with a thin layer of jam, and top with the chopped Curly Tops chocolate.
Cut each circle into 12 equal wedges, and roll them up, starting at the wide end, bending each pastry into a crescent shape.
Place the pastries on parchment-lined baking sheets, and preheat the oven to 350°F.
Brush the pastries with egg wash and sprinkle with sparkling sugar.
Bake for 27-29 minutes, or until golden.