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Making royal icing today, for a rather overdue Christmas cake.I always end up with too much icing sugar, based on my normal recipe which asks for 4 large egg whites and 500g icing sugar.So today I used 3 egg whites and as much icing sugar as "felt right". Is this fair enough? If it's taking a long time for stiff peaks to form, is this a sign of too little icing sugar? And if I overdid the icing sugar how would I tell?
Royal icing - how important is accurate measuring?