Set the eggs out that you’ll need for the frosting. By the time you bake and cool the cupcakes, the egg whites will be room temperature.

Make the confetti cupcakes. Allow them to completely cool.

Place egg whites, sugar, and cream of tartar in a heatproof bowl. Set bowl over a saucepan filled with two inches of simmering water. Do not let it touch the water. (You can use a double boiler if you have one.) Whisk constantly until sugar is dissolved, about 4 minutes. You can use a candy thermometer to make sure they’re ready; it will register 160°F (71°C).*

Transfer the mixing bowl to an electric mixer fitted with a whisk attachment. Add the vanilla. Beat on high speed for 5-6 minutes until soft, glossy peaks form. (See photo above.) Taste. Add a pinch of salt if needed. I like to add 1/8 teaspoon of salt.

Pipe frosting onto each cooled cupcake. I use a Wilton 1M tip. You may have an extra cupcake or 2 leftover if you use a lot of frosting on each cupcake. Chill cupcakes in the refrigerator or freezer until frosting is completely firm. I freeze mine for 20 minutes.

melt the chopped chocolate and oil together in the microwave in 20 second increments, stirring after each until completely melted. You can also melt in a double boiler if you have one. Let the chocolate cool down for 5-10 minutes before dipping.

Holding the cupcake by its bottom, carefully and very quickly dip each into chocolate to coat the frosting. Place on a wire rack on top of a baking sheet in case any chocolate drips off. The perfect shape of the piped frosting may slightly deflate—that’s ok! Add any additional sprinkles on top. Refrigerate cupcakes for 30 minutes to set the chocolate.

Cover and store cupcakes at room temperature for 1 day or in the refrigerator for up to 1 week. Finished cupcakes do not freeze well.