In a stand mixer with a paddle attachment or a large bowl with a hand mixer beat the room temperature butter and sugar together until creamy and fluffy.

Add in the egg yolks and vanilla extract and mix until combined. Scrape the sides of the bowl and the bottom of the bowl to make sure the butter is evenly mixed. On low speed add in the dry ingredients and then increase to medium speed. It will not come together like dough instead the consistency will be almost like a shaggy pie crust where you have to knead it to come together.

Add the powdered sugar to your stand mixer. In a small bowl add corn syrup, meringue powder, and clear vanilla extract and mix. Slowly add the mixture to the powdered sugar and mix on low for 15 seconds and then medium to high speed for 5 minutes. Slowly adjust the consistency of the royal icing by adding more water. Divide the royal icing into medium-sized bowls and add gel food coloring

Cuff the piping bags over a tall cup and pour the royal icing into each bag. I like to divide up the colors into 3 or 4 small bags, so everyone gets their piping bag. You can get technical and add a coupler and a piping tip too if you want to decorate them nicely.