TOTAL TIME: 2 hours
DIFFICULTY: 3
SPECIAL EQUIPMENT: stand mixer, standard 12-cup muffin tin, pastry bag (or zip-top bag) with small round piping tip
CAKE
1-3/4 cups (7-1/2 ounces) unbleached all-purpose flour
1 teaspoon baking powder
1/4 teaspoon kosher salt
8 tablespoons (4 ounces) chilled unsalted butter, cut into 1/2-inch cubes
1 cup (7 ounces) granulated sugar
2 large eggs plus 1 egg yolk
1/2 teaspoon orange extract
1/2 teaspoon vanilla extract
1 cup freshly squeezed orange juice (from 3 or 4 oranges)
FILLING
2 large egg whites
1/2 cup (3-1/2 ounces) granulated sugar
1/2 teaspoon vanilla extract
1/4 teaspoon cream of tartar
ORANGE FROSTING
2 cups (8 ounces) powdered sugar
2 teaspoons light corn syrup
1/2 teaspoon orange extract
1/4 cup whole or reduced-fat milk
3 ounces white chocolate, coarsely chopped (a scant 1/2 cup)
WHITE DOODLE ICING
1/2 cup (2 ounces) powdered sugar
1 teaspoon whole or reduced-fat milk
1 teaspoon light corn syrup
MAKE THE CUPCAKES:
Preheat the oven to 350°F. Spritz the wells of a standard 12-cup muffin tin with baking spray.
Whisk the flour, baking powder, and salt together in a large bowl, sifting if needed to remove any lumps.
In the bowl of a stand mixer fitted with the paddle attachment, beat the butter and sugar together for 2 to 3 minutes on medium speed, until the butter is pale and fluffy. Reduce the mixer speed to low and add the eggs and yolk one at a time, mixing thoroughly before adding the next. Add the orange and vanilla extracts and stir for 15 seconds to combine.
Add a third of the flour mixture, stirring until just combined, then half the orange juice. Repeat with a third more flour mixture and the remaining orange juice, then the final portion of the flour mixture.
Divide the batter evenly among the prepared muffin wells. Bake for 15 to 20 minutes, until the cupcakes are set in the middle. Remove the cupcakes from the muffin tin and cool to room temperature on a wire rack.
MAKE THE FILLING:
While the cupcakes bake and cool, fill a small, straight-sided saucepan halfway with water and bring to a simmer over medium-low heat. Place the egg whites and sugar in a heatproof stainless steel or Pyrex bowl and set the bowl over the simmering water. Whisk continuously for 1 to 2 minutes, until the sugar dissolves and the liquid is slightly opaque and frothy, and warm to the touch.
Transfer the whisked egg whites to the bowl of a stand mixer fitted with the whisk attachment. Whip on medium-high speed for about 2 to 3 minutes, until the liquid becomes opaque and glossy. Add the cream of tartar and vanilla and whip for 1 to 2 more minutes, until stiff peaks form when the mixer is turned off and the whisk is lifted.
MAKE THE FROSTING:
Stir the powdered sugar, corn syrup, orange extract, and milk together in a heatproof metal or glass bowl. Set over the simmering water and cook, stirring, until warm to the touch. Add the chopped white chocolate and cook, stirring constantly, until the chocolate is melted. Remove from the heat.
Use a sharp paring knife to cut a deep, wide hole in each cupcake, leaving a 1/2-inch border of cupcake. Spoon filling into each hole, using a mini spatula or spoonula, and spread flush with the top of the cupcake.
Dip the top of each filled cupcake in the white chocolate glaze, letting excess glaze drip back into the bowl. Set on a wire rack to allow the glaze to set for at least 30 minutes.
MAKE AND PIPE THE DOODLE ICING:
Whisk the powdered sugar, milk, and corn syrup together in a small bowl until a thick glaze forms. Fill a pastry bag or gallon-size zip-top bag fitted with a small round piping tip with the icing (see How to Fill a Pastry Bag, page 187).
Pipe circles of icing down the center of each cupcake top. Let sit for at least 1 hour to let the frosting and icing firm up.
The cupcakes can be made a day in advance and kept at room temperature. They should be eaten within 3 days.