• Spread your ice cream out in a 9 x 13-inch cake pan, making sure it’s in an even layer.
• Put the pan in the freezer for later.

Make the Cookies:

• Combine the sugars and butter in a large mixing bowl.
• Use an electric hand mixer to cream the ingredients together on medium high speed for 2 minutes, or until smooth and creamy.
• Whisk in the egg and vanilla until just combined.
• Add the flour, baking powder, and cocoa powder to the mixing bowl.
• Gently whisk the dry and wet ingredients together until no pockets of dry flour remain.
• Cover your cookie dough with plastic wrap and let it rest in the fridge for 30 minutes.

Bake the Cookies:

• Preheat the oven to 350°F.
• Place the cookie dough on a large sheet of parchment paper.
• Roll it out into a rectangle about 9 x 13 inches and put it on a large baking sheet.
• Bake the cookie dough for 12 minutes.
• Slice the sheet of cookie dough into 10 smaller rectangles as soon as it comes out of the oven.
• Let the cookies cool in the fridge for 30 minutes.

Assemble the Ice Cream Sandwiches:

• Once the cookies have cooled, take your tray of ice cream out of the freezer and slice 5 rectangular squares about the same size as your cookies.
• Sandwich a square of ice cream between 2 cookies and place your ice cream sandwiches on a tray.
• Freeze the ice cream sandwiches for an hour before serving.