This is it: the easy way to go about making ice cream cakes. I promise you they will be stunners and that you won’t have to spend hours in your kitchen. My ice cream cake has a meringue base because in my mind, a cake involves baking and an ice cream cake made of only ice cream is just round ice cream. The meringue sort of melts into gooey, chewy deliciousness during freezing, but I like that. If you want a more substantial base for your cake I suggest you try a brownie recipe, or maybe even just make a large chocolate chip cookie as your base. Feel free to play around with the recipe and make it your own!
Preheat your oven to 300°F (150° C). Cover the bottom of a springform pan with parchment paper and make a ring to cover and peak over the sides of the pan like a collar. Brush some vegetable oil on the side of the pan and stick the parchment paper collar in place.
Make the meringue. Whip the egg whites in a clean bowl until soft peaks form. (You can do this by hand but it's easier to use a mixer.) Next, add the sugar one tablespoon at a time with the mixer running. When you have added all the sugar, you should be left with a beautiful, creamy, thick meringue mixture. Sift the cornstarch and cocoa powder into the meringue mixture and fold it in using a large spoon or spatula. Add the vinegar and fold that in carefully, too.
Pour the meringue mixture into your prepared pan and smooth it out to the edges with the help of a spatula. Set the pan in your preheated oven and bake for 1 hour. Turn the oven off and let it cool down completely with the oven door closed. Remove the meringue from the oven and set aside.
When your meringue base is completely cooled, start on your ice cream.
Mix the whipping cream with the sweetened condensed milk until stiff peaks form. Stir in the vanilla extract and divide the mixture in two. You now have two bowls of ice cream base. Sift the cocoa powder over one of the mixtures and stir until you have an even chocolate ice cream base. Add about a third of the chocolate pieces to the other mixture and stir. You now have the three necessary elements for your ice cream cake: the meringue base, and two types of ice cream mixtures.
Pile the two ice cream mixtures alternatively onto your meringue base (this is when the collar comes in handy, as your ice cream may peak over the rim of your pan).
Lift your pan a couple of centimeters above your work surface and drop it so that your mixture falls evenly into place and you get a smooth top. Using a skewer, blend the two ice creams ever as much as you'd like. Cover the surface with plastic wrap (try to get the plastic wrap as close to the ice cream as possible without touching it), and freeze over night.
If you plan to decorate your cake with chocolate trim, put the remainder of the finely chopped chocolate in a piping bag. Insert the piping bag into a glass of hot water (be careful not to get any water in your chocolate) and let the chocolate melt. Remove your cake from the freezer and take off the plastic wrap. Carefully peel away the paper collar. Pipe the melted chocolate over your cake or around the rim like I did.
Put the cake back into the freezer, or serve it immediately. Lift the cake carefully from the bottom of the pan and remove the paper, then place it on a cake stand or platter. To serve the cake, use a good, steady knife and dip it in hot water before making each slice. A hot knife makes for smoother cutting.