1. Sift the powdered sugar. Sift 3 1/2 cups (1 pound) powdered sugar through a fine-mesh strainer into a large bowl. If any lumps are left in the strainer, use your fingers to break them up and push them through the strainer.

2. Measure the egg whites. Place 4 large pasteurized egg whites or 1/2 cup liquid egg whites in the bowl of a stand mixer fitted with a whisk attachment. (Alternatively, use an electric hand mixer and large bowl.)

3. Whip the egg whites until foamy. Whip on medium-high speed until foamy, doubled in volume, and opaque, about 2 minutes.

4. Beat in the powdered sugar. Turn the mixer off and add half of the powdered sugar. Mix on low speed until the powdered sugar is completely dissolved and no large lumps remain, 1 to 2 minutes. Add the remaining powdered sugar and continue mixing until completely dissolved, 1 to 2 minutes more.

5. Whip until smooth and glossy. Increase the mixer speed to high and whip until the icing is completely smooth, glossy, and slightly thickened, 4 to 5 minutes. The icing should hold a soft peak and slowly run off of the whisk attachment. If the icing is too loose, add more powdered sugar, 1/4 cup at a time, and continue mixing until completely incorporated.

6. Add optional extracts and food coloring. Decrease the mixer speed to low and add 1 teaspoon extract and a few drops of food coloring, if desired. Mix until the icing is smooth and evenly colored, 1 to 2 minutes.

7. Adjust the consistency with water. The icing can be used as-is or thinned out with water to achieve a pourable consistency for flooding cookies. Add water in 1 teaspoon increments, stirring between each, until desired consistency is reached. If not using immediately, press a sheet of plastic wrap directly on the surface of the frosting to keep it from drying out until ready to use.

8. Decorate cookies with the icing and let dry. Decorate cookies with the icing and let completely dry before touching them, at least 4 hours.

Recipe notes

Royal icing can be refrigerated in an airtight container with a sheet of plastic wrap pressed directly onto the surface for up to one week. When ready to use, adjust the consistency as needed with water.

Consuming raw egg whites will always come with some inherent risks. That’s why we recommend using pasteurized eggs, which are gently heated, to reduce the risk of food-borne illnesses. All egg products in the United States are pasteurized as required by the USDA — so you’re good to go as long as you stick to eggs from the grocery store (don’t use ones that come straight from the farm).

(Jesse Szewczyk is studio food editor for TheKitchn.com, a nationally known blog for people who love food and home cooking. Submit any comments or questions to editorial@thekitchn.com.)

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