Preheat your oven to 110 degrees Celsius (230 F)
Line baking sheets with baking paper
In the bowl of a stand mixer add the egg whites, cream of tartar and salt. Starting on a low speed whip the egg increasing the speed to medium until the egg white bubbles are small and uniform, and when you lift the beaters soft peaks form. This can take some time, you want to check that all the egg white has been whipped and that there is no liquid egg white in the bottom of the bowl.
Increase the speed to high and begin adding the caster sugar steadily. I do this by adding the sugar a tablespoon at a time until all the sugar has been added.
Once the caster sugar has been added, add the vanilla and beat until stiff peaks have formed.
Remove the mixing bowl from the stand mixer and sift one-third of the icing sugar over the glossy whipped egg whites. Fold this in using a spatula. Repeat with the next third of the icing sugar and then the final third.
Add three-quarters of the chocolate drops to the meringue and carefully fold through.
Spoon large spoonfuls of the meringue onto the lined baking paper to form your meringue cookies.
Top the cookies with a few of the remining chocolate chips.
Bake for 1 hour and 15 minutes, before turning off the oven and leaving the meringues in the oven to cool completely.
Enjoy!