• Preheat your oven to 350°F and line a 24-cup muffin pan with paper liners.

Make the Cupcakes:

• In a large mixing bowl, combine the yellow cake mix, buttermilk, vegetable oil, eggs, and 2 teaspoons of vanilla extract.
• Beat on medium speed for 2 minutes until the batter is smooth and well combined.
• Divide the batter evenly among the muffin cups, filling each about two-thirds full.
• Bake in the preheated oven for 15 to 22 minutes or until a cake tester or toothpick inserted into the center comes out clean.
• Remove from the oven and allow the cupcakes to cool in the pan for 10 minutes before transferring them to a wire rack to cool completely.

Make the Frosting:

• In a large mixing bowl, beat the butter on medium speed until creamy and smooth.
• Gradually add the powdered sugar, a cup at a time, mixing well after each addition.
• Add vanilla extract, kosher salt and heavy cream.
• Beat at high speed for 2 or 3 minutes until the frosting is light and fluffy.
• If the frosting is too thick, add an additional tablespoon of cream; if it’s too thin, add a bit more powdered sugar.

Decorate the Cupcakes:

• Once the cupcakes have cooled completely, generously frost each one with buttercream frosting.
• Form a small amount of edible Easter grass into a nest and place it on top of each frosted cupcake.
• Put a marshmallow Peep in the center of each nest.
• Add a couple of robin egg chocolates beside each Peep to resemble eggs in the nest.