Beat the butter and cream cheese together until smooth, then mix in the flour and salt just until a soft dough forms.

Divide the dough into 4 disks, wrap each in plastic, and chill at least 1 hour, until firm enough to roll without sticking.

Mix the sugar and cinnamon in a small bowl.

Roll one disk at a time on a lightly floured surface into a 9-inch circle.

Spread a thin layer of apricot jam over the circle, then sprinkle with a quarter of the cinnamon sugar and a quarter of the chopped gelt.

Cut the circle into 12 wedges, like a pizza.

Roll each wedge up from the wide end to the point, curving slightly into a crescent as you go.

Repeat with the remaining dough, arranging the rolled cookies point-down on parchment-lined baking sheets.

Chill the shaped cookies 15 minutes while the oven heats to 350°F.

Brush each cookie with egg wash and bake 20 to 22 minutes, until golden and the chocolate has just started to peek through the seams.

Cool on the pan 5 minutes before moving to a rack, so the melted chocolate has a moment to firm back up.