You'll need two batches of frosting to decorate all of these coconut-studded cupcakes, but be sure to make each batch separately. The frosting will start to harden if not used immediately.
For the Cupcakes
- 1 3/4 cups all-purpose flour
- 1/2 cup fine unsweetened coconut flakes, finely ground in a food processor
- 2 teaspoons baking powder
- 1 1/2 sticks unsalted butter, room temperature
- 1 1/2 cups sugar
- 2 large egg yolks, plus 5 large egg whites, room temperature
- 1 1/2 teaspoons pure vanilla extract
- 3/4 cup unsweetened coconut milk
For One Batch of the Seven-Minute Frosting (makes about 4 cups; enough for 12 cupcakes)
- 3/4 cup plus 1 tablespoon sugar
- 1/3 cup water
- 1 tablespoon light corn syrup
- 3 large egg whites, room temperature
- Garnish: large unsweetened coconut flakes
Preheat oven to 350 degrees. Make the cupcakes: Line 2 standard muffin tins with baking cups. Whisk together flour, ground coconut flakes, baking powder, and 1/2 teaspoon salt in a large bowl. Beat butter and sugar with a mixer on medium speed until pale and fluffy. Add egg yolks and vanilla. Reduce speed to low. Add flour mixture in 3 additions, alternating with coconut milk, beginning and ending with flour, beating well after each addition.
Whisk egg whites in a clean bowl of a mixer on medium speed until stiff peaks form (do not overmix). Working in 3 batches, gently fold egg whites into cupcake batter.
Divide batter evenly among baking cups, filling each two-thirds full. Bake until cupcakes are pale golden and centers spring back when touched, 18 to 2o minutes. Let cool in tins on wire racks.
Make the first batch of seven-minute frosting: Heat 3/4 cup sugar, the water, and corn syrup in a small saucepan over medium heat, stirring occasionally, until sugar dissolves. Raise heat to medium-high, and bring to a boil. Cook until syrup reaches 230 degrees on a candy thermometer.
Meanwhile, beat egg whites with a mixer on medium speed until soft peaks form, 2 to 3 minutes. With machine running, add remaining tablespoon sugar.
Once syrup is ready, immediately remove from heat. With mixer on medium-low speed, pour syrup down side of bowl into egg-white mixture. Raise speed to medium-high, and beat until mixture is completely cool and stiff peaks form, about 7 minutes.
Immediately frost half of the cupcakes, each with 1/3 cup frosting, and garnish with 1 or 2 teaspoons large coconut flakes. Prepare another batch of frosting, and frost remaining cupcakes.