1/4 cup butter, softened
1/3 cup sugar
1/3 cup brown sugar, firmly packed
1 large egg
2 teaspoons vanilla
1 1/4 cups flour
1 cup walnuts, toasted (divided)
1/4 teaspoon baking soda
1/4 teaspoon salt
2 tablespoons pure maple syrup
2 tablespoons packed brown sugar
a pinch of cinnamon
Beat butter, sugar and brown sugar with an electric mixer for 1 minute, until well combined, beat in egg and vanilla until smooth. In a second bowl, combine flour, baking soda and salt. Put half the walnuts into the bowl of a food processor and pulse until finely ground. Add to the flour mixture. Combine contents of both bowls and stir by hand just until you have a soft dough.
Roll the dough between two sheets of waxed paper into a 12-inch square. Place on a cookie sheet in the fridge for about 30 minutes or in the freezer for about 15 minutes.
Make the filling: put the remaining walnuts into the food processor and pulse until coarsely chopped, add the brown sugar and cinnamon, stir well.
Remove dough from the fridge and peel off the top layer of waxed paper.
Drizzle the maple syrup evenly over the dough, then sprinkle with the brown sugar /walnuts mixture, going almost to the edges. Gently roll into a log, peeling back the bottom paper as you go. Wrap in waxed paper or plastic wrap and freeze for 3 hours, or up to 3 months.
When ready to bake, preheat oven to 350F. Slice the log into 1/4-inch slices and place on a cookie sheet that has been lined with parchment or sprayed with non-stick spray.
Bake for 12-15 minutes, until pale golden. Let cool on the sheet for a few minutes before transferring to a wire rack to cool.