This classic cookie is downright irresistible, with its brown-sugar dough wrapped around the sumptuous sweetness of dates, the whole flecked with walnuts for crunch. If you're not a date-lover, there's no reason to deprive yourself; just try the cranberry filling instead. Many holiday cookie swaps just wouldn't be complete without a tray of these cookies.
In a large bowl, cream together the butter and brown sugar. Add the eggs one at a time, beating well after each addition. Scrape the sides and bottom of the bowl, then stir in the flour, salt and baking soda.
Place the dough in a large plastic bag, press it flat, and refrigerate for 1 hour, or until it's firm enough to roll out. This allows the dough to cool more quickly and gives you a head start when it's time to roll out the dough.
To make the date filling: Combine the dates, sugar, water, and salt in a medium saucepan over medium-high heat. Bring to a boil, reduce the heat to medium, and boil gently for 15 minutes, or until the mixture has thickened to the consistency of soft jam. Stir in the nuts and set aside to cool to room temperature.
To make the cranberry filling: Place all of the ingredients except the nuts in a medium saucepan. Cover and cook over medium heat until the mixture comes to a boil. Uncover and cook, stirring occasionally, until the cranberries pop and the mixture thickens to the consistency of jam. You should be able to see the bottom of the pan for 5 seconds when you pull a spoon through the mixture. Remove from the heat, stir in the nuts, and allow the mixture to cool to room temperature before using it to fill the pinwheel dough.
To shape the cookies: Divide the dough in half. Working with one half at a time, roll the dough into a 9" x 12", 1/4"-thick rectangle on a lightly floured piece of parchment or waxed paper. Spread half the filling (date or cranberry) over the entire surface of the dough.
Using the paper to help you, roll the dough from the long edge into a log. Wrap the dough and chill for several hours, or overnight. (To keep the soft log of dough in shape as it chills, use the cardboard core from a roll of paper towels or wrapping paper, slit lengthwise. Once the dough is wrapped, pop it inside the cardboard tube; the tube will support the dough till it's set.) Repeat with the remaining dough and filling.
When you're ready to bake, preheat the oven to 400°F. Lightly grease (or line with parchment) two baking sheets. Remove the dough from the refrigerator and let it rest for 10 minutes, so it won't crack when you cut it.
Slice each log into 1/3" slices, and place the slices 2" apart on the prepared baking sheets. When slicing the rolled cookies, give the dough a quarter turn after each cut; this will keep a flat spot from developing on the roll as you cut.
Bake for 8 to 10 minutes, or until the cookies are light brown. Remove from the oven, let them rest on the baking sheet for 3 minutes, then transfer them to a rack to cool.
