Gingersnap Ice Cream Sandwiches

Preheat oven to 350 degrees. Cream butter, granulated sugar, and molasses until fluffy. Beat in yolk. Whisk flour, baking soda, salt, and spices in a small bowl. Fold into butter mixture 1/3 at a time. Roll dough into eight 1 1/2-inch balls, spacing them 2 inches apart on parchment-lined baking sheets. Press to form 3-inch disks. Sprinkle with sanding sugar if desired. Bake, rotating halfway through, until golden around edges, 11 to 13 minutes. Transfer cookies to a wire rack, and let cool.

Scoop ice cream onto 4 cookies and top each with a second cookie. Freeze until firm. Let stand 10 minutes before serving.