Preheat the oven to 225 degrees.
In a standing mixer, add in the egg whites and cream of tartar.
Mix on medium speed until soft peaks form and then increase to faster speed.
Alternating between the sugar and powder sugar, add in 1 Tablespoon at a time until stiff peaks form.
Add in the vanilla and mix until combined.
Split batter into 5 bowls:
Add blue into one bowl.
Add pink into the second one.
Add orange into the third one.
Add yellow into the fourth one.
Leave the fifth bowl white.
Using a pastry bag with a round tip, scope some blue meringue on 1/4 of the bag.
Add the pink meringue to another 1/4 of the bag.
Add the orange to the bag.
Add the yellow and then the white.
Pipe on the meringues onto a baking sheet lined with parchment paper.
Bake for 90 minutes.