Sift Confectioners' Sugar.
I personally weigh it so I know the quantity is exactly 2.25 pounds and this makes a difference in how my royal icing turns out.
Place it in a bowl of a stand mixer. If you don’t have a stand mixer place it in a medium-sized mixing bowl.
Place the water, meringue powder, and flavor in a jar and mix it well. If you place it in a Mason jar and shake it, it will be frothy.
Pour it in the confectioner’s sugar.
Add the paddle attachment and mix it on the lowest speed until the confectioner’s sugar starts mixing with the wet ingredients.
Turn the mixer up a little and mix for about a minute or two.
Scrape the sides of the bowl and continue to mix until the icing looks smooth, thick, and creamy.
Place the royal icing into an airtight container.
Cover it with a piece of plastic wrap making sure it’s touching the top of the royal icing. This will prevent the air from crusting and drying the top layer of the icing.
Place the lid on the container.
When you’re ready to decorate, tint the icing with soft food gel colors, and decorate.