Spray two baking tins with nonstick spray and dust liberally with icing sugar.

In the bowl of an electric mixer, soak the gelatine in the cold water. Set the bowl over a double boiler and allow the gelatine to melt. Remove from the heat.

Add the castor sugar and boiling water. Attach the bowl to the mixer, using the whisk attachment. Beat on high speed for 8–10 minutes until the mixture is thick and shiny.  Add the rosewater and stir through. Add food colouring, a few drops at a time, until your desired hue is reached.

Pour into the prepared pans to a thickness of 3 cm. Refrigerate  before cutting the marshmallow into shapes and dusting with icing sugar. Decorate with fresh raspberries (optional).