Fill a pot (large enough for your metal mixing bowl to sitting securely) with water about a 1/4 full. Test with your bowl to make sure that the bottom of the bowl is not touching the water.
Remove your bowl and heat the water to simmer.
Meanwhile, place the egg whites and cream of tartar in the bowl.
Using a hand whisk, beat until the mixture is foamy.
Add the sugar to the egg mixture and mixture with the whisk.
Place the metal bowl on top of the pot and continue to whisk until the sugar has melted and you can no longer feel the graininess of the sugar, when rubbed between your fingers.
Transfer the metal bowl to a stand mixer or you can use a handheld mixer.
Beat on a high until soft peaks are formed.
Add the vanilla extract at this point.
Continue to beat on high until stiff peaks are formed. Mixture should look like clouds or melted marshmallows, be glossy and hold a peak should should hold its shape when beater is removed from the mixture.
Sift the malted milk, coffee powder and vanilla powder if using, into the meringue and gently fold it in.
Place the meringue mixture into a piping bag
Pipe small rounds of meringue onto a baking tray lined with parchment paper. While you could use a silicone baking mats, I have found that my cookies will become chewier rather than crispier. But feel free to use either.
Bake the meringues for an hour.
At the hour mark, turn the oven off and leave meringues in the oven for about an hour or until oven has cooled down to room temp or you need to use the oven again.