-
1
Preheat oven to 350 degrees F. Line two 12-cup cupcake tins with paper liners.
-
2
(To avoid cupcakes sticking if they overflow slightly, lightly spray the tops of the pans.)
-
3
Put tins on a baking sheet.
-
4
Set aside.
-
5
Process sugar and butter in a food processor until very creamy, scraping sides as needed, 1 to 2 minutes.
-
6
Add the eggs and yolks, one at a time, pulsing after each addition.
-
7
Add the milk, water, and vanilla and process to blend.
-
8
Whisk both flours, baking powder, and salt in a medium bowl.
-
9
Add the dry ingredients, in 3 batches to the wet, pulsing, and then scraping batter off the sides of the processor as needed after each addition.
-
10
Process until the batter is very smooth and pourable like pancake batter, about 2 minutes.
-
11
Evenly pour the batter into the prepared cups, filling them 3/4 of the way full.
-
12
Bake until the cakes are just firm and spring back when gently pressed, and the tops are golden, 18 to 25 minutes.
-
13
Cool slightly in tin, and turn out of tin when cool enough to handle.
-
14
Cool cupcakes completely on a rack before frosting.
-
15
Whisk the milk and vanilla extract together in a small bowl.
-
16
Slowly beat the butter and sugar, in another medium bowl, with an electric mixer until incorporated.
-
17
Raise the speed to high and mix until light and fluffy, about 5 to 7 minutes.
-
18
(Occasionally turn the mixer off, and scrape the sides of the bowl down with a rubber spatula.)
-
19
Add the fluff and salt and reduce the speed to low.
-
20
Add the milk and vanilla mixture, scrape the bowl down, and mix until fully incorporated.
-
21
Raise the mixer to high and beat briefly until fluffy, about 1 to 2 minutes.
-
22
Use immediately.
