Using store-bought cake makes this trifle easy enough to prepare anytime, and for no special occasion, though it is also just right for a casual summer gathering with friends. Canned condensed milk is used in the custard, for extra richness. The strawberries are allowed to macerate with sugar and fresh orange juice to draw out their juices and also be infused with flavor. Be sure to allow enough time for the assembled dessert to chill before serving.