To prepare the brownie layers:

1. Preheat the oven to 350 degrees. Line two quarter sheet pans (or two 9”x13” pans) with foil that extends up the sides and grease with baking spray. Set aside.
2. In a small saucepan over low heat, gently heat the dark chocolate and butter, stirring regularly, just until barely melted. Pour the mixture into a large bowl and whisk in the sugar and brown sugar. Whisk in the eggs and the vanilla extract. Scrape the sides of the bowl and then fold in the flour, cocoa powder, and salt. Fold in the chocolate chips. Spread the batter evenly between the two pans and bake in the preheated oven for about 11-12 minutes or until a toothpick inserted only comes out with a few moist crumbs. Set aside to cool completely.

To prepare the sandwiches:

1. Once the brownie layers have cooled, flip them one layer out of the pan. In a large bowl or the bowl of a stand mixer, whip the cream on medium-high speed until thick and fluffy. Add the vanilla extract and continue beating until stiff peaks form. Fold in the sweetened condensed milk and cookie crumbs. Spread the thick filling on top of the brownie layer still inside the prepared pan. Smooth the top as much as possible and then place the second brownie layer directly on top. Gently press down to adhere, but avoid squishing the ice cream out the sides. Place in the freezer to freeze completely, about 6 hours. Use a 3” cookie or biscuit cutter to trim out sandwiches or use a chef’s knife to cut square. Keep frozen and covered until ready to eat!