Make the Crust + Cookie Crumbs

1. Mix together the chocolate graham cracker crumbs, sugar and salt in a medium bowl. Pour in the melted butter and mix until the crumbs are fully moistened. Scoop out half of the crumbs into a 9-inch wide, 3-inch deep spring form pan that's been sprayed with cooking spray. Use the bottom of a glass or measuring cup to press the crumbs into the bottom of the pan, forming an even layer that creeps up about an inch on the sides. Take the remaining crumbs and spread them out onto a parchment-lined baking sheet. Place both pans in the freezer to set up for a minimum of 30 minutes.

Make the Ganache

1. Heat the heavy cream in a medium saucepan over medium-high heat until it just starts to bubble. Remove from the heat and pour in the chocolate chips. Stir until the chips are fully melted, and the ganache is smooth and shiny.

Make the Salted Caramel

1. Place the sugar and corn syrup in a medium saucepan over medium heat and swirl the pan around gently until the sugar melts. Try to avoid stirring unless absolutely necessary. Cook the sugar until it starts to turn amber in color, then remove from the heat and add in the heavy cream and butter. Be very careful, as it will bubble up and foam immensely at this point. Rapidly stir until everything is incorporated. Place the pot back on the stove and cook over medium heat until it turns a shade or two darker. Keep a close eye on it, as you don't want it to go too far. Remove it from the heat, and stir in the salt and vanilla. Allow to cool to room temperature before assembling the cake.

Assemble

1. Remove the spring form pan from the freezer and pour half of the ganache over top. Spread it out into an even layer, then sprinkle with a teaspoon of flaky sea salt. Place the pan back in the freezer for 30 minutes.
2. Remove the pan from the freezer, and scoop out one half gallon of vanilla ice cream. Spread the ice cream out evenly, pressing it down so there are no air bubbles or gaps. Place back in the freezer for 30 minutes.
3. Remove the sheet pan of chocolate crumbs from the freezer and crumble into small pieces. Remove the spring form pan from the freezer and pour 2/3 of the chocolate crumbs over the layer of ice cream. Next, pour 3/4 of the salted caramel over the chocolate crumbs, then place back in the freezer for another 30 minutes.
4. Remove the spring form pan from the freezer and scoop out the remaining half gallon of ice cream. Spread it out over the caramel layer, pressing down to remove any air bubbles or gaps. Place back into the freezer for 30 minutes.
5. Remove from the freezer and pour the remaining ganache over the top, spreading it out into an even layer. Crumble the last of the chocolate crumbs over top, then douse with the remaining salted caramel, and top with a teaspoon of flaky sea salt. Place back in the freezer for one more hour, or until ready to serve.
6. When ready to serve, remove the cake from the freezer and run the outside of the pan under hot running water, being very careful to not let any touch the top. Release the hinge on the side of the pan, and remove the sides. To cut, dip a long, sharp knife in HOT water for a few seconds, and then slice into the cake. Repeat for every slice.