Make the filling

1. Place the dates with the jam in a blender jar and pulse until the dates are smooth. 
2. Scoop the date mix into a small pan and heat it over medium just until it comes to a boil. 
3. Stir the walnuts and cloves into the dates.
4. This filling can be made up to a week ahead of time (just pop it in the fridge, covered).

Make the dough log

1. Using a paddle attachment on a stand mixer, mix the powdered sugar, butter and egg yolk until just combined.
2. Add in the vanilla and the salt to the butter to combine. The mixture should be well-combined but not fluffy.
3. Pour in the flour, then pulse the mixer a few times before letting it run just long enough for the flour to disappear–about 10 seconds. Turn off the mixer, and use a baking spatula

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   to squish in any flour that’s hanging out at the bottom of the bowl. 
4. Place two large pieces of plastic wrap together on the counter.  Scoop the dough into the middle of the plastic, and then use the edges of the plastic to press the dough into a rectangular log.  Divide the dough into 5 pieces.
5. Line the bottoms and sides of a 8.5” x 4.5” loaf pan with plastic wrap. 
6. Roll each portion of dough into a rough rectangle.  Place one of the portions of dough between two pieces of plastic.  Use a small rolling pin

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   or a double ended rolling pin

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   to roll the dough into a rectangle that’s close to the size of the pan. Peel the dough off the plastic and then press the sheet of dough into the pan so that it covers the bottom.  You may need to press the dough into the corners.
7. Roll a quarter of the filling into a rough log and then roll it between the same pieces of plastic into a sheet just as you did with the dough.  Peel off the date filling (it will look like a fruit roll-up) and place it on top of the dough.  Alternatively, you can spoon out filling enough to cover the dough, using the spoon to smooth it out.  If the filling doesn’t entirely cover the dough, feel free to add a little extra pinch of the filling to cover the dough in a thin layer.
8. Keep rolling the dough and filling, alternating layers of dough and filling ending with dough on top. 
9. Bring the overhanging plastic of the dough around all the layers.  Wrap it well and then pop the loaf pan in the freezer to freeze for at least 2 hours or up to 1 month ahead.

Baking the cookies

1. When you’re ready to bake, preheat the oven to 350 F (180 F). Line 2 baking sheets with parchment

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   paper.
2. Cut and bake: Cut the loaf in half down the short side, and then cut 1/4″ slices of dough. Bake for 20-22 minutes until the bottoms are lightly browned and the cookies are firm.
3. Cool and enjoy: Let the cookies cool thoroughly on the baking sheets. Store cookies in an airtight tin for up to 2 weeks. You can also freeze them for up to 2 months.