Blackberry Pistachio Icebox Cake

"[Photograph: Max Falkowitz] I love icebox cakes in the summer, when the thought of turning on an oven is too much to bear. This cake veers a bit from tradition, adding blackberries, pistachios, and pomegranate molasses in between layers of tea biscuits and rose water-infused whipped cream. It's sweet and creamy like an icebox cake should be, but tart berries and nutty pistachios keep things interesting. Rose water complements the fruity flavors and deepens the nutty notes; a perfect accent to an easy, but delicious, warm-weather dessert...."