Step 1
Preheat the oven to 350 degrees (175 degrees C). Line the bottom of a 9-inch cake pan with parchment and spray the sides with cooking spray.
Step 2
Melt butter semisweet chocolate chips and unsweetened chocolate in a medium mixing bowl set over a double boiler stirring frequently. Remove from heat and let cool while working on the next step.
Step 3
Combine flour baking powder and salt in a small mixing bowl.
Step 4
Whisk sugar eggs instant coffee and vanilla together in another bowl until well combined. Pour in the chocolate mixture and stir to combine. Add in the flour mixture and stir until fully incorporated. Pour batter into the cake pan.
Step 5
Bake in the preheated oven until edges are set and a toothpick inserted into the middle comes out clean about 35 minutes. Cool completely in the pan at least 30 minutes.
Step 6
In the meantime transfer ice cream to the refrigerator to warm for 15 minutes. Line a 9-inch glass mixing bowl with plastic wrap leaving a few inches of overhang on the sides.
Step 7
Remove one of the pints of pistachio ice cream and press into the bottom of the prepared bowl using a small rubber spatula. Smooth into an even layer and freeze for 15 minutes. Repeat the process with both pints of strawberry ice cream freezing for 15 minutes between each pint.
Step 8
Fold the overhanging plastic wrap over the top layer of ice cream. Freeze until solid 10 hours to overnight.
Step 9
Turn brownie out wrap in plastic wrap and refrigerate overnight.
Step 9
Gently whisk egg whites with superfine sugar and cream of tartar over top of a double boiler until eggs are warm to the touch the sugar has dissolved about 5 minutes. Pour meringue into the bowl of a stand mixer fitted with a whisk attachment. Whip at a low speed until foamy. Increase speed and beat until stiff glossy peaks form 5 to 6 minutes. Stir in vanilla.