Makes 12 cupcakes

1 1/2 cups (6 oz/171 g) cake flour

1 1/4 teaspoons baking powder

1/4 teaspoon salt

1/2 cup (1 stick/4 oz/113 g) unsalted butter, softened

1 cup (7 oz/200 g) granulated sugar

2 large eggs

2 teaspoons finely grated orange zest

3 tablespoons (1 ½ ounces/45 ml) freshly squeezed strained orange juice

1/3 cup (80 ml) whole milk

1 cup (2 sticks) unsalted butter, softened

3/4 cup 85 g) confectioners’ sugar

1/4 cup (58 g) heavy cream

1/2 teaspoon vanilla extract

2 cups (113 g) confectioners' sugar

3 tablespoons strained fresh orange juice

1 tablespoon orange-flavored liqueur

Orange food coloring

Royal Icing Squiggle:

2 ½ cups (284 g) confectioners' sugar

3 tablespoons liquid pasteurized egg whites

1 tablespoon warm water

1. Position a rack in the center of the oven and preheat the oven to 350°F. Line a standard 12-cup muffin pan with cupcake liners.

2. In a medium bowl, sift together the cake flour, baking powder, and salt. Whisk to combine and set aside.

3. In the bowl of an electric mixer, using the paddle attachment, beat the butter at medium speed until creamy, about 30 seconds. Gradually add the sugar and beat at high speed for 3 minutes, until well blended and light. Scrape down the sides of the bowl with a rubber spatula, reduce the speed to medium, and add the eggs one at a time, beating well after each addition and mixing until blended. Beat in the orange zest and the orange juice until blended (the mixture will look curdled at this point). Reduce the speed to low and add the flour mixture in three additions, alternating it with the milk in two additions. Mix just until blended. Scrape the batter into the prepared muffin cups, dividing it evenly. Bake the cupcakes for 18 to 22 minutes, until they are a light golden brown and a toothpick inserted into the center of a cupcake comes out clean. Cool the cupcakes in the pan, set on a wire rack, for 5 minutes. Transfer the cupcakes to the wire rack and cool completely.

4. In an electric mixer, using the paddle attachment, beat the butter at medium speed until creamy, about 1 minute. Gradually add the confectioners’ sugar and beat at high speed until, about 3 minutes. Add the cream and beat for another minute. Scrape the filling into a pastry bag fitted with a 1/4-inch plain or star tip.

5. Use a paring knife to cut a small X in the center of the bottom of each cupcake. Hold a cupcake upside-down, letting your fingers rest on the top of the cupcake (which is now the bottom). Poke the pastry tip three-quarters of the way into the cupcake and squeeze in some filling, stopping when you feel a slight pressure on the top of the cupcake. Repeat with the remaining cupcakes. Set the filled cupcakes aside while you make the glaze.

6. Sift confectioners' sugar into a small saucepan and stir in orange juice and liqueur to make a smooth paste. Heat glaze over moderately high heat until just warm to the touch. Remove from heat and stir in some orange food coloring.

7. Leave the glaze in the saucepan on low heat. Dip each cupcake top in the glaze, letting the excess drip off. You may need to stir the glaze in between glazing each cupcake to ensure that it’s smooth. 

8. Combine all the Royal Icing ingredients in the bowl of an electric mixer fitted with the paddle attachment. Beat on high for 5 minutes, scraping down the bowl occasionally (the icing should be fairly thick—if it seems too thin, add more confectioners’ sugar and beat until smooth). Scrape some Royal Icing it into a small parchment cone or a pastry bag fitting with a writing tip. Pipe a row of curlicues horizontally across the center of each cupcake. Serve the cupcakes at room temperature or slightly chilled. They can be stored, covered, in the refrigerator for up to 3 days.