Start by weighing the egg whites. I had about 100g of egg whites so I had to double their weight in sugar, meaning 200g. I replaced some of sugar with the flavoured sugar (1/4 the quantity was quite enough)
Preheat the oven at 100 C / Gas 1/4. Line a baking tray with greaseproof paper.
Beat the whites until stiff then sprinkle the sugar over the whites and continue to beat till stiff. Transfer to a piping bag and squirt small meringues onto the baking tray.
Bake in the oven for 90 minutes.
Tap gently on the meringue with your finger. If it seems hollow inside then the meringue is done.