Preheat your oven to 350°F (175°C). In a mixing bowl, beat together 1 cup of softened unsalted butter and 1 cup of granulated sugar until light and fluffy, about 5-7 minutes.

Add 2 large eggs to the mixture, mixing until fully incorporated. Gradually mix in 3 cups of all-purpose flour and 2/3 cup of finely chopped walnuts on low speed.

Shape the dough into logs about 1-1/2 inches thick and slice into 1/4 inch rounds. Place cookies on ungreased baking sheets, leaving space for spreading.

Bake for 10-12 minutes or until bottoms are lightly golden brown. Let cool completely on wire racks.

To prepare the filling, combine 2 cups of dried apricots and 3/4 cup of water in a saucepan and cook for about 10 minutes until tender. Blend with 1/4 cup of sugar and 1/2 teaspoon of ground cinnamon until smooth.

Assemble the cookies by spreading the apricot filling on the flat side of one cookie and topping with another cookie. Repeat with remaining cookies.

Melt 1/2 cup of semisweet chocolate chips and 1/2 teaspoon of shortening, then drizzle over assembled cookies. Dust with 4 teaspoons of confectioners' sugar if desired.