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.
Scoop out one half gallon of vanilla ice cream and spread it out evenly on top of the ganache, pressing it down so there are no air bubbles or gaps. Place back in the freezer for 30 minutes.
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 ⅔ of the chocolate crumbs over the layer of ice cream. Next, pour ¾ of the salted caramel over the chocolate crumbs, then place back in the freezer for another 30 minutes.
Scoop out the remaining half gallon of ice cream and spread it out over the caramel layer, pressing down firmly to fit it all in. Make sure there are no air bubbles or gaps, then place back into the freezer for 30 minutes.
Pour the remaining ganache over the top and spread 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 up to one week before serving.