Try any of our different fillings in this traditional cream cheese dough cookie for a variety of options -- each more delicious than the other.
Place the flour and salt in the bowl of a food processor, and pulse until combined. Add the butter, and pulse 10 times. Add the cream cheese; pulse until the mixture is just combined. Drizzle in the buttermilk; pulse until the mixture just comes together when you press it with your fingers.
Transfer dough to a clean work surface, and shape into a flat disk; cover with plastic, and refrigerate at least 3 hours or overnight.
Heat oven to 375 degrees. Line two baking sheets with parchment; set aside. In a small bowl, combine filling ingredients of your choice. Set the filling aside.
Divide chilled dough into three pieces. Flatten one into a disk, and return other two to refrigerator. On a lightly floured work surface, roll out the disk to an 1/8-inch thickness. Cut dough into a 6 1/4-inch circle. Using a pizza cutter, divide the dough in half, then into quarters, then into eighths.
Brush each triangle lightly with jam, then sprinkle with 1 teaspoon filling mixture, being careful not to cover the narrow ends. Starting at the wider end, roll up each cookie; transfer to a baking sheet. Brush each cookie with egg white, then sprinkle with nuts and sanding sugar. Chill until firm, about 15 minutes. Repeat with remaining two-thirds of dough.
Bake cookies until golden brown, 15 to 20 minutes. Transfer baking sheets to a wire rack to cool completely. Store in an airtight container up to 2 days.