01 -
Preheat the oven to 350 F. Line an 18 by 13 inch rimmed sheet pan with parchment paper, leaving overhang on the long sides.
02 -
Whisk the sugar, oil, eggs, and vanilla in a large bowl until smooth. Stir in the cocoa powder, flour, and salt just until combined.
03 -
Spread the batter evenly in the prepared pan. Bake for 16-18 minutes, until the center is set and a toothpick comes out with a few moist crumbs.
04 -
Cool completely in the pan. Lift out with the parchment and cut the chocolate sheet crosswise into two equal rectangles.
05 -
Spread the softened ice cream over one chocolate rectangle in an even layer. Place the second rectangle on top and press gently to level it.
06 -
Wrap the assembled slab tightly and freeze for at least 3 hours, or until very firm all the way through.
07 -
Use a warm, dry knife to cut into 15 sandwiches. Roll the edges in mini chocolate chips or sprinkles if desired, then serve or wrap individually for storage.