When I make a layered gelatin salad, the layers slide off one another. What am I doing wrong? —C.H., Orient, South DakotaOur Test Kitchen has found that this happens when a layer of gelatin is poured onto another layer that is set up too firmly. Try chilling each layer of gelatin until it is set, but not firm, about 15-20 minutes, before adding the next layer of gelatin. The surface of the gelatin should be slightly sticky.