Beat egg whites until stiff. Bring sugar and 50 ml water to the boil while stirring. Whip the hot sugar syrup with the beaten egg white. Continue beating for a few minutes until the beaten egg white has stabilized. Pour the mixture into a piping bag with a large perforated spout and squirt lightly on 12 biscuits. Chill for about 30 minutes.
Melt the couverture with coconut oil over a warm water bath. Carefully spread the liquid chocolate on the meringue with the help of a spoon. Place on baking paper and chill until the icing has set. Store in the refrigerator.