There are a million boiled frosting recipes floating around the internet, and they go by a million names. Boiled frosting, cooked flour frosting, heritage frosting, ermine frosting, and I'm sure there are many aliases I've missed. As far as the ingredients and the proportions go, they're pretty much all the same--flour, sugar, milk, butter, and flavoring. Grandma's version doesn't deviate as far as that goes, but the technique is a bit different than the recipes I've seen. It guarantees a light, fluffy, and silky smooth frosting that's more stable than a powdered sugar based frosting, and not too sweet.
<br />It's also really versatile. The recipe my Grandmother made was pretty much always vanilla, but you can change the flavor easily by substituting another extract, a teaspoon of instant espresso powder, or an ounce of melted and cooled unsweetened chocolate when the instructions say to add the flavoring.

Read the recipe on Food52.com