1. Make cookie crumb mixture. A package of Oreos is divided into three sections. Scrape the icing out of two sections of cookies then run cookies through food processor. Mix cookie crumbs with just enough hot fudge to coat crumbs. Crumb mixture should be a little sticky but not runny.
2. Spread a 1-inch thick layer of vanilla ice cream around the outside of a 9-inch spring-form pan. This will give the ice cream cake a uniform outside look if you take it out of the ring and display it on a cake stand. This is the most difficult part of the process so if you don’t care about how it looks on the outside, don’t worry about trying to line the outside of the pan. Just coat the bottom of the pan with a 1-inch layer of vanilla ice cream.
3. Fill in center of cake half way with strawberry ice cream.
4. Sprinkle cookie crumb mixture over the cake. Make sure you save around 1/4 to 1/2 cup of cookie crumb mixture for later. (The cookie crumbs are my favorite part of ice cream cake so I went with a pretty thick layer!)
5. Using a rubber spatula, spread a layer of hot fudge over the top of the cookie crumbs. Make sure the hot fudge is room temperature, otherwise it will melt the whole cake.
6. Add another layer of strawberry ice cream and then a layer of vanilla. Cover and freeze overnight or for at least 6 hours.
7. Coat top of ice cream cake with whipped cream. Sprinkle the remaining cookie crumb mixture on top of cake and garnish with left over Oreos. Cover and freeze for overnight or for another 6 hours.