These Vanilla Bean Cupcakes are tender and fluffy and topped with ultra creamy mascarpone buttercream frosting made with real vanilla beans! They're perfect for parties, birthdays, or any occasion at all!
Preheat your oven to 350 degrees Fahrenheit and prepare muffin tins with 18 paper muffin cups.
Add the butter and white sugar to the bowl of your stand mixer and mix on high speed until light and fluffy, scraping down the sides of the bowl a few times.
Continue mixing on high and add the eggs one at a time, stopping the mixer and scraping down the sides of the bowl after each addition.
Combine the flour, cornstarch, baking powder, and salt in a medium bowl and set aside.
Measure the milk and scrape the vanilla bean seeds into the milk, stirring well to combine.
Add the flour mixture and the milk mixture alternatively to the butter mixture, mixing on low speed until everything is added (start and end with the dry ingredients).
Mix on high speed for about one minute to ensure everything is combined.
Divide the batter between the 18 prepared muffin cups and bake at 350 degrees Fahrenheit for about 17-19 minutes.
Whip the butter and mascarpone on high speed until light and fluffy.
Add the powdered sugar one cup at a time, whipping on high speed between each addition and scraping down the sides of the bowl.
Scrape the seeds out of the vanilla bean and add them to the frosting, along with the heavy cream and salt.
Whip on high until well combined, scraping down the sides of the bowl.
Cool the cupcakes completely on a wire rack.
Add the frosting to a large piping bag fitted with a large star tip and pipe the frosting onto the cooled cupcakes.
Store in the fridge for 24 hours before serving, or serve immediately.
These cupcakes keep in the fridge for up to 2 days in an airtight container.
These cupcakes freeze well before they're frosted, and keep in the freezer for up to 3 months. Simply thaw and frost before serving.