Chocolate Chip Ice Cream Sandwich Bars

Preheat the oven to 350°F. Line a 13" x 18" rimmed baking sheet (half-sheet pan) with parchment and lightly grease the parchment. 

Melt the butter and whisk in the brown sugar. Add the salt and vanilla, stirring until smooth. 

If the mixture is uncomfortably hot to the touch, allow it to cool a bit before adding the eggs all at once. Whisk until smooth.   

Stir in the flour and baking powder. 

By this time, the batter should be no more than lukewarm; stir in the chips. Use a spatula to spread the batter in the prepared pan, making a thin, even layer all the way to the edges.  

Bake the bars for 14 to 18 minutes, until they’re set in the middle and just starting to turn golden brown. Remove from the oven and cool completely before assembling the sandwiches. 

Meanwhile, remove the cookie bar from the baking sheet and cut it in half vertically to make two pieces approximately 8 1/2" x 12" each. 

Line a 9" x 13" pan with plastic wrap, allowing it to generously overhang on all sides. Place one of the bars in the pan, top side up. 

Top the bar with the partially thawed ice cream. Spread it to the edges, leaving about 1/2" on every side bare. 

Place the other bar on top of the ice cream, top side down, gently pressing down to evenly spread the ice cream to the edges. It’s OK if some of the ice cream oozes out the sides. 

Using the overhanging wrap, completely cover and tightly wrap the assembled sandwich.  

Place the pan in the freezer overnight.

For the neatest look, trim the edges off the sandwich (baker's treat!). Cut into bars that are the size and shape of your choice.  

Dip the edges of each bar into the topping of your choice; we like sparkling sugar, cocoa nibs, or sprinkles. Serve immediately. 

Store the cut bars, individually wrapped, in the freezer for up to three months.  

These bars keep exceptionally well in the freezer. Feel free to make them well ahead for any summertime celebration. 

Be sure to use mini chips in these bars, or break full-size chips into smaller pieces. Larger (standard) chips can be unpleasantly hard when frozen.