Step 1

Preheat the oven to 350°F. Line two muffin cups of a standard size muffin tin with cupcake liners. Set aside.

Step 2

In a small mixing bowl, stir together the butter and vegetable oil with a whisk or fork (you can also use a handmixer to make things go faster!) until smooth and combined. If your butter is too cold, you can microwave the mixture for a few seconds to soften it up!

Step 3

Add the sugar and mix until light and fluffy and pale in color, about 1 minute. Add the egg white, milk, and vanilla extract and mix well.

Step 4

Add the flour, baking powder, and salt and use a small rubber spatula to fold the mixture together until no streaks of flour remain.

Step 5

Use a silicone spatula to scrape the batter evenly into the prepared muffin cups. Bake until the cupcakes have domed up, resist light pressure, and a butter knife inserted in the center of the cupcake comes out with just a few moist crumbs attached, 20 to 25 minutes.

Step 6

While the cupcakes cool, make the frosting. In a small mixing bowl, whisk together the butter, powdered sugar, milk, vanilla extract, and salt. Mix until fluffy and combined.

Step 7

Transfer the frosting to a piping bag fitted with a small round tip (don’t feel like piping? You can also just spoon the frosting on top!). Pipe the frosting onto the two cupcakes. Top with sprinkles, if desired. Serve.