This lemon raspberry mousse cake is a refreshing dessert that is perfect for a summer day. The cake is made with a lemon sponge cake, layered with a creamy raspberry mousse, and topped with fresh raspberries. The mousse is made with fresh raspberries, whipped cream, and gelatin, giving it a light and airy texture. The lemon sponge cake adds a tangy flavor to the cake, making it a perfect dessert for a summer barbecue or picnic.