Cream butter and sugar. Add egg and vanilla and mix well. Blend flour, cocoa powder and salt until well combined. Blend with butter mixture.

Divide into two balls and chill for a half hour. (see note)

Take one piece of dough out of the refrigerator. Roll out on a floured 8 x 12 inch parchment paper to 8 x 8. Leave two inches of parchment on each end of the dough. Set the dough topped parchment paper into the baking pan with two ends extending out (so you can pull out the final ice cream sandwiches)

Cream butter and sugar. Add egg and vanilla and mix well. Blend flour, cocoa powder and salt until well combined. Blend with butter mixture. Divide into two balls and chill for a half hour.

Take one piece of dough out of the refrigerator. On an 8 x 12 inch piece of floured parchment roll to 8 x 8. Leave two inches of parchment on each end of the dough. (You may want to use a second piece of floured parchment on top for rolling.) Set the dough topped parchment paper into the baking pan with two ends extending out (so you can pull the final ice cream sandwiches out of the pan)

Roll out the second piece between floured parchment to 8 x 8 then score into six “sandwich-sized” pieces. Using a baking thermometer or other pointed object, poke with evenly spaced holes. Place on a second baking sheet to bake.

Remove top and bottom sandwich layers from freezer. Leave the bottom (un-scored) cookie layer in the pan and top with softened ice cream. Set the top (scored) layer on top of the ice cream. (Don’t worry if the top breaks along the score lines since you’ll be cutting it apart later.) Cover and place back in the freezer overnight.

The next day or when ice cream is very hard, run knife along the sides of pan without the parchment to loosen. Remove sandwiches from the pan by pulling up on the parchment. Cut sandwiches apart and wrap each one separately.