Pecan Dulce de Leche Sandwich Cookies

3/4 cup butter, softened
1/4 cup each granulated sugar and packed dark brown sugar
1 egg yolk
1 tsp. vanilla
Pinch salt
2 cups all-purpose flour
3/4 cup finely chopped toasted pecans
1/4 cup unsweetened desiccated coconut, toasted
1/2 cup dulce de leche

In large bowl, beat together butter, granulated sugar and brown sugar until fluffy; beat in egg yolk, vanilla and salt. In separate bowl, stir together flour, 1/2 cup of the pecans and coconut; stir into butter mixture in 2 additions to make smooth dough.

Divide dough in half; form each into 1 1/2 inch wide log. Roll each in remaining pecans, pressing to adhere. Wrap each and refrigerate for 1 hour or for up to 24 hours.

Cut logs into 1/4 inch thick slices. Arrange, 1 inch apart, on parchment paper-lined baking sheets. Bake in 350 degree oven until golden, about 10 minutes. Transfer to rack; let cool completely.

Spread bottoms of half of the cookies with about 1/2 tsp. dulce de leche each. Top with remaining cookies to make sandwiches. Makes about 36 cookies.