Moist Vanilla Cupcakes

Introduction

These vanilla cupcakes are the gold standard for a reason, achieving a supremely moist and tender crumb with a perfect, fluffy vanilla buttercream. You’ll love the professional bakery-quality results from using a unique combination of sour cream and whipped egg whites for the ultimate texture.

Prep & Cook Time

Prep Time: 15 minutes

Cook Time: 20 minutes

Total Time: 35 minutes

Servings: 16 cupcakes

Ingredients

For the Cupcakes:

• 1 2/3 cup all-purpose flour (213g)
• 1 cup granulated sugar (200g)
• 1/4 tsp baking soda
• 1 1/2 tsp baking powder
• 1/4 tsp kosher salt
• 3/4 cup unsalted butter (170g, melted)
• 3 egg whites (room temperature)
• 1 tbsp vanilla extract (15mL)
• 1/2 cup sour cream (120mL, room temperature)
• 1/2 cup whole milk (120mL, warm)

For the Vanilla Buttercream:

• 2 lb confectioners sugar (900g, sifted)
• 1 lb unsalted butter (450g, room temperature)
• 1 tsp vanilla extract
• 1 tbsp heavy cream
• 1 pinch kosher salt
• 1 tsp whole milk

Instructions

1. Preheat your oven to 350°F (175°C). Line a standard muffin tin with 16 cupcake liners.
2. In a large bowl, whisk together the all-purpose flour, granulated sugar, baking soda, baking powder, and kosher salt.
3. In a separate medium bowl, combine the melted butter, room temperature egg whites, vanilla extract, sour cream, and warm whole milk. Whisk until smooth.
4. Divide the batter evenly among the 16 prepared cupcake liners, filling each about 2/3 full.
5. Bake for 18-20 minutes, or until a toothpick inserted into the center of a cupcake comes out clean.
6. Let the cupcakes cool in the pan for 5 minutes, then transfer them to a wire rack to cool completely before frosting.
7. To make the buttercream, beat the room temperature butter with an electric mixer on medium-high speed for 5 minutes until pale and very fluffy.
8. Reduce mixer speed to low and gradually add the sifted confectioners sugar, about one cup at a time, until fully incorporated.
9. Add the vanilla extract, heavy cream, and pinch of kosher salt. Beat on medium-high speed for another 2-3 minutes until very light and creamy. If the frosting is too thick, add the 1 teaspoon of whole milk.
10. Pipe or spread the buttercream onto the completely cooled cupcakes.

Variations

• Swirl & Sprinkle: Use an open star piping tip to create a classic swirl of frosting and finish with colorful sprinkles.
• Filled Cupcakes: Use a piping tip or apple corer to remove a small plug from the center of each cooled cupcake, then fill with a dollop of jam or lemon curd before frosting.
• Chocolate-Dipped: Instead of frosting, dip the tops of the cooled cupcakes into melted chocolate and let set for a glossy, elegant finish.
• Flavor Infusion: Add a teaspoon of citrus zest (like lemon or orange) to the cupcake batter or buttercream for a bright twist.

Tips for Success

• Ensure all dairy ingredients (egg whites, sour cream, milk) are truly at room temperature; this helps them emulsify properly for an even, fine crumb.
• Sift the confectioners sugar for the buttercream to avoid any lumps and to create a silky smooth frosting.
• Warm the milk for the cupcake batter slightly (about 30 seconds in the microwave) to help it blend smoothly with the melted butter without causing it to solidify.

Storage & Reheating

FAQ

Can I use whole eggs instead of just egg whites?

Yes, but the crumb will be slightly denser and the color will be more yellow. The egg whites contribute to a very light, fluffy texture.

Why is the milk for the cupcake batter warmed?

Warm milk helps it integrate smoothly with the melted butter without causing the butter to clump or solidify, ensuring a uniform batter.

My buttercream is too thick. What can I do?

You can add the extra teaspoon of whole milk specified in the frosting ingredients, or add more heavy cream one teaspoon at a time until you reach your desired consistency.

Can I make the cupcakes ahead of time?

Absolutely. Bake and cool them completely, then freeze unfrosted cupcakes in an airtight container for up to 2 months. Thaw at room temperature before frosting.

What can I use if I don’t have sour cream?

Full-fat plain yogurt is the best substitute. Avoid low-fat options as the fat content contributes to the moist texture.

Is kosher salt different than table salt?

Yes, it is less dense by volume. If you only have table salt, use half the amount called for to avoid over-salting your batter.