Add whites to the bowl of an electric mixer and beat on medium-low for 1-2 minutes to let bubbles begin to form.
Increase speed to medium and beat until soft peaks form.
With the mixer still running, slowly begin adding the sugar, about 1 tbs at a time, until all the sugar has been used. Increase the speed to medium-high, then continue beating until stiff peaks form. Test the meringue between your fingertips to ensure there are no sugar granules left.
Add vanilla, then beat for 30 more seconds.
Fill a piping bag with the meringue and pipe out "kiss" shaped meringues.
Bake until solid enough to come off the paper easily, about 35 to 40 minutes.
Remove from oven and let cool completely on baking sheet. Once they've cooled completely, draw on little beaks and eyes with the icing.
In a medium saucepan not yet on the heat, whisk together sugar, cornstarch, and salt. Pour in about a third of the milk, and whisk thoroughly, to dissolve the corn starch. Add the rest of the milk and the egg yolks, whisk to break the yolks and mix in.
Whisking constantly, heat over medium until large bubbles form and pop. Reduce heat to low then cook another minute, while continuing to whisk. Remove from heat and transfer to a bowl or heatproof measuring cup. Stir in butter, vanilla, and food coloring. Cover with plastic wrap directly touching the surface, then chill completely in the fridge. It could take 1 to 3 hours. You could also make this ahead of time and keep it in the fridge for up to 3 days.
Preheat oven to 350 F and like 24 standard sized cupcake tins with paper liners.
Sift together cocoa, flour, baking powder, and salt. Set aside.
In a large mixing bowl, cream together butter and sugar until light and fluffy. Beat eggs in one at a time, then beat in the vanilla.
Decrease the mixer's speed to low, then begin adding the sour cream and flour. Start with some flour, switch to some of the sour cream, switch back to flour, etc, and continue alternating until all has been mixed in.
Divide the batter between the paper cups, filling each about 3/4 full. Bake until they pass the toothpick test, about 20 minutes.
Remove from oven and let cool completely before topping.
Once the cupcakes have cooled, use a piping bag or butter knife to distribute the pastry cream between the cupcakes. Place a meringue chick on each, revel in the cuteness, and enjoy!