Strawberry and White Chocolate Mousse Ladyfinger Cake

Some cakes are impossible to make without a cake ring or springform pan because the liquid filling needs to be held in place while it sets. Unlike springform pans, which have a base that holds the cake even after the sides of the springform pan are taken off, cake rings are just rings. To support the cake and seal it in the ring, you need to cut out a circle of cardboard that fits snugly into the bottom of the ring. It is also a good idea to line the ring with plastic wrap before you put in