Preheat the oven to 200C / 400F / Gas Mark 6.
Sieve the icing sugar, the flour and the salt into a large bowl. Beat the egg whites until they form soft peaks and fold in the beaten egg whites, the melted butter, vanilla essence and single cream.
Mix the batter until well combined and then put in the fridge for at least one hour.
Put 2-4 ladlefuls of batter on a greased baking tray (depending on the size of your tray), making sure there is space for each to spread a little.
Bake in the oven for six minutes and just when the edges begin to brown, remove from the oven. With a spatula, put the first pancake on a work surface and quickly roll into a 'cigarette' shape. You have to do this fast as they harden very quickly. If the edges begin to crack, pop the tray back into the oven to soften again.
Repeat steps 4-5 until you have used all of the batter. When the 'cigarettes' are completely cold use an icing bag with a very narrow nozzle to fill each cigarette with Strawberry Conserve.
Sprinkle with the icing sugar and serve immediately.