Then, to cover or «flood» the entire surface of the cookie with icing, add a little water to make the icing thinner. (joyofbaking.com)
For this border the royal icing needs to be thicker than the recipe given below which is used to spread over the entire surface of the cookie. (joyofbaking.com)
To cover or «flood» the entire surface of the cookie with icing, the proper consistency is when you lift the beater, the ribbon of icing that falls back into the bowl remains on the surface of the icing for a few seconds before disappearing. (joyofbaking.com)