Stage 1: Bake and Prepare the Brownie Layers

1. Prepare Oven and Pan:

• Preheat the oven to 350°F (175°C).
• Line an 18×13-inch rimmed baking sheet (a standard half sheet pan) with a large piece of foil, making sure to leave at least a 2-inch overhang on the two longer sides. This foil “sling” is crucial for lifting the brownie out later.
• Generously butter the foil.

2. Make the Brownie Batter:

• In a medium bowl, whisk together the all-purpose flour, unsweetened cocoa powder, and fine salt. Set aside.
• Melt the 2 sticks of butter and the chopped chocolate in a medium saucepan over medium-low heat, stirring frequently until smooth.
• Remove the saucepan from the heat and let the chocolate mixture cool slightly for a few minutes.
• Stir the granulated sugar into the slightly cooled chocolate mixture.
• Add the slightly beaten eggs and stir until well combined.
• Add the prepared flour mixture to the saucepan and stir with a spatula just until all the ingredients are combined. Do not overmix.

3. Bake and Chill the Brownie:

• Pour the brownie batter into the prepared foil-lined pan. Using an offset spatula or the back of a spoon, spread the batter into a thin, even layer that covers the entire surface of the pan.
• Bake for 20 to 25 minutes. The brownie is done when a toothpick inserted in the center comes out with just a few moist crumbs adhering to it (not wet batter).
• Let the brownie cool completely in the pan on a cooling rack.
• Once cool, place the entire pan in the freezer to firm up, for about 30 minutes.

Stage 2: Assemble the Giant Ice Cream Sandwich

1. Prepare the Brownie Slabs:

• Use the foil overhangs to carefully lift the entire chilled brownie slab out of the pan.
• Carefully flip the brownie over onto a large cutting board. Peel the foil away from the bottom and discard it.
• Line the now-empty baking sheet with a large piece of plastic wrap.
• Using a long, sharp knife, trim the rough edges off the brownie so it is an even rectangle. The recipe suggests trimming to 16-by-12 inches.
• Cut the trimmed brownie in half crosswise, resulting in two pieces that are approximately 12-by-8 inches each.

2. Assemble and Freeze:

• Lay one of the brownie pieces, top-side facing down, onto the prepared plastic wrap-lined baking sheet.
• Let your coffee ice cream soften at room temperature for a few minutes until it is just spreadable but not melty. Work quickly!
• Using a large ice cream scoop or a spatula, spread the softened coffee ice cream evenly across the brownie on the baking sheet, getting it close to all the edges. Use an offset or rubber spatula to help smooth out the sides and top of the ice cream layer.
• Place the other brownie piece on top of the ice cream and press down gently to create one large ice cream sandwich.
• Fold the overhanging plastic wrap around the assembled ice cream sandwich to help hold its shape and keep it tightly wrapped.
• Return the giant sandwich to the freezer to harden completely. This will take at least 6 hours, but overnight is ideal.

Stage 3: Cut and Coat the Sandwiches

1. Cut into Sandwiches:

• Remove the giant frozen brownie ice cream sandwich from the freezer and unwrap it. Place it on your cutting board.
• Using a large, sharp knife warmed under hot running water and wiped dry, carefully cut the large block into twenty-four individual ice cream sandwiches (e.g., cut into 6 rows by 4 rows).

2. Coat and Serve:

• Place the chopped chocolate-covered espresso beans in a shallow dish or on a plate.
• Working with one sandwich at a time, roll the exposed ice cream edges into the chopped espresso beans until the sides are well coated.
• Wrap each finished sandwich individually in parchment paper and enjoy immediately, or return to the freezer to store.
• These sandwiches will keep, well-wrapped, in the freezer for up to 1 week for best texture.