Decorated Christmas Sugar Cookies with Royal Icing

Dough that keeps its shape

Most cut-out disasters come from warm dough. Use softened but cool butter (a finger leaves a dent but doesn't sink in), cream it with the sugar for only about 1 minute, and keep the leavening low. This recipe has just 1/2 tsp baking powder so the edges stay sharp.

Roll the dough between two sheets of parchment to 1/4 inch (6 mm) right after mixing, then chill the flat sheets. They firm up in 30 minutes instead of the 2 hours a ball takes, and you never work in extra flour that makes cookies dry. Rolling guides, or a chopstick laid on each side of the dough, keep the thickness even so every cookie bakes in the same time.

Bake at 350°F (175°C) for 8–11 minutes depending on size. Pull them when the tops look matte and the edges are set but not browned. Re-roll the scraps once only, because a third roll makes them tough. In a hot kitchen, such as an Australian December, put each tray of cut shapes in the freezer for 10 minutes before it goes in the oven.

Royal icing: two consistencies, measured in seconds

Make one stiff base batch, then thin it. Outline icing is like toothpaste and holds a ridge. Flood icing is the 15-second kind: drag a knife through the bowl and the line should vanish in about 15 seconds.

Add water by the 1/2 teaspoon, not the tablespoon. Going too thin is the most common mistake: thin icing runs off the edges, forms craters, and can take a day to dry. If you overshoot, stir in powdered sugar 1 tablespoon at a time.

Color with gel coloring, because liquid drops thin the icing. Red and dark green deepen as they sit, so mix those first and stop a shade lighter than you want. A no-taste red gel gets there with far less coloring. Keep every bowl covered with plastic wrap pressed onto the surface, since royal icing crusts in minutes.

For kids or a no-fuss session, mix everything to a single 20-second consistency so one bag both outlines and floods.

Region notes:

• UK: royal icing sugar (just add water) replaces powdered sugar plus meringue powder, and plain flour is the all-purpose flour.
• Australia: use pure icing sugar, not icing mixture, which contains cornflour. Tablespoons there are 20 ml, so weigh the meringue powder (about 28 g).
• No meringue powder: use 3 large pasteurized egg whites (about 6 tbsp / 90 ml) per 1 lb (454 g) of powdered sugar, and leave out most of the water.

Where to spend the time

Use the waiting time. Make the icing while the dough chills, and finish coloring it while the cookies cool. Cookies must be completely cool (20–30 minutes on a rack) before icing, or the icing melts and slides.

Spend your patience on flooding. Save time on details by adding sprinkles to wet flood icing instead of piping fine lines. When a dark color sits right next to white, let the first section crust for about 1 hour before piping the second against it, or the red bleeds into the white.

Shortcuts and scaling:

• The classic shortcut is splitting across two days: bake on day one, store the plain cookies airtight, and decorate on day two.
• Undecorated cookies freeze for up to 3 months.
• One dough batch and one 1 lb icing batch make about 24 cookies of 3 inches. For a cookie swap of 4–5 dozen, double everything and mix the dough in two batches if your mixer is small.

How to tell it worked

Good cookies have corners as sharp as the cutter, matte pale tops, golden color only underneath, and edges that feel firm when you press them lightly.

Good icing sits level inside the outline without dripping over the edge, and is dry to a light touch after about 1 hour. Leave the cookies uncovered 6–8 hours or overnight before stacking, bagging or packing tins. Humid weather slows this, and a fan on low blowing across the trays speeds it up.

Packed airtight at room temperature, decorated cookies keep 1–2 weeks.