• Before you start making the cupcakes, preheat your oven to 325 degrees Fahrenheit and line two 12-cup muffin tins with paper liners. 
• Then, in a medium-sized bowl, whisk together your flour, baking powder, baking soda, and salt. Set it aside. In a liquid measuring cup, whisk together your milk and sour cream until no lumps remain. 
• In a stand mixer with the paddle attachment, cream your butter, sugar, and vanilla on medium speed until the mixture is light and fluffy (around three to five minutes). Scrape the sides, as well as the bottom of the bowl and the paddle. 
• Turn your mixer to medium speed and slowly add the egg whites a little at a time, making sure they're incorporated before adding more. Stop the mixer and scrape down the sides, bottom of the bowl, and paddle again. 
• Then turn your mixer to low speed and add the flour mixture in three additions, alternating with the milk mixture and beginning and ending with the dry ingredients. Mix everything for about 15 seconds, just until it's incorporated. 
• Stop the mixer and remove the bowl. Scrape down the bowl and the paddle. 
• Then, evenly scoop the batter into your prepared muffin cups (Lloyd recommends using a ¼ dry measuring cup). Bake your cupcakes for 20-22 minutes, until the tops spring back when touched and a cake tester inserted into the centers comes out clean. 

Vanilla Buttercream Frosting

• First cream the butter on medium speed in a stand mixer with the paddle attachment for three to four minutes, until it's light and fluffy.
• Add the vanilla and mix for one minute, then scrape down the bottom and sides of the bowl. 
• With the mixer running on low speed, gradually add the powdered sugar, one cup at a time. Scrape down the bottom and sides of the bowl again. When you have added the third cup of sugar, the mixture will start to thicken and appear dry. 
• Add three tablespoons of the milk, then add the rest of the sugar — add more milk if the buttercream is too stiff. The desired consistency is creamy and smooth. Scrape down the bottom and sides of the bowl. 
• Continue to beat the icing on low speed for one to two minutes longer, until it's smooth and creamy. Do not mix on medium or high, as it will add too much air and be too fluffy. Add a few drops of your desired food coloring — one drop at a time — and mix thoroughly to get the right color. 
• Use an icing wand to spread your buttercream over the cupcakes until they're fully covered. Top with a daisy decoration. You can store any extra icing at room temperature in an airtight container for up to three days.