1cupcarrots, peeled and finely grated (4 1/2 ounces)
½cupwhole buttermilk,room temperature
½cupdark brown sugar,lightly packed
1 ½cups + 2 tbspall-purpose flour,spooned and leveled
1 ½tspbaking powder
¼tspcoarse Kosher salt(if using table salt, use half the amount)
4ozcream cheese,softened to room temperature
½cupunsalted butter,softened to room temperature
2 ½cupspowdered sugar
⅛tspcoarse Kosher salt(if using table salt, use half the amount)
1tspvanilla extract or vanilla bean paste
Preheat the oven to 350 F and line two standard-sized muffin pans with 18 paper liners.Note: If you only have one 12-cup pan, you can bake the cupcakes in batches, and let the batter rest at room temperature until you're ready to bake the second batch. Scoop the batter into the pan without mixing it up again.
Melt the butter in a saucepan over medium low heat. Continue cooking, swirling occasionally, until nutty brown solids form on the bottom of the pan. Immediately scrape the butter and the browned bits into a large mixing bowl and let cool for 5 minutes.
Add the carrots, applesauce, oil, buttermilk, granulated sugar, brown sugar, eggs and vanilla to the brown butter, and whisk until smooth.
In a separate bowl, sift together the flour, baking powder, salt and spices.
Add the dry ingredients to the wet, and whisk for 10-15 seconds until combined.
Use a scant 1/4 cup measuring cup to fill the paper liners about 2/3 - 3/4 full. Bake the cupcakes on the center oven rack for about 17 minutes, until the tops spring back when gently touched.
Let the cupcakes cool in the pan for 5 minutes, then gently transfer to a cooling rack to cool completely before frosting.
In the bowl of your stand mixer fitted with the paddle attachment, beat the cream cheese and butter for 1 minute until smooth.
With the mixer on low, add the powdered sugar and the meringue powder, mixing until combined.
Add the salt and vanilla; on medium high, whip for several minutes until light and fluffy – add a little more powdered sugar if the buttercream is too soft, or 1-2 tablespoons milk or cream if it's too thick.
Fit a piping bag with tip 1M, fill with the buttercream, and pipe swirls or rosettes on the cooled cupcakes.
Leftover cupcakes should be kept refrigerated, in an airtight container or cupcake carrier, for up to 3 days. Bring the cupcakes to room temperature before serving.
Keyword Brown Butter, Carrot Cake, Cream Cheese Frosting, Cupcakes, High Altitude