Make the Meringue:
Preheat oven to 250°F (120°C) and line a baking sheet with parchment paper.
In a clean, dry mixing bowl, beat egg whites with an electric mixer on medium speed until foamy.
Add cream of tartar and continue beating while slowly adding the sugar, one tablespoon at a time.
Beat until stiff, glossy peaks form (about 5-6 minutes).
Gently fold in cocoa powder, vanilla extract, and melted chocolate (if using) until combined.

Shape the Nests:
Spoon the meringue into a piping bag fitted with a large star tip (or use a spoon to shape nests).
Pipe or shape small nest circles (about 3 inches wide) on the prepared baking sheet.
Use the back of a spoon to make a small indentation in the center of each nest.

Bake & Cool:
Bake for 1 hour, then turn off the oven and let the meringues cool inside for another 30 minutes to prevent cracking.

Decorate & Serve:
Fill the center of each nest with whipped cream or chocolate ganache.
Top with chocolate eggs, jelly beans, or malted milk eggs.
Sprinkle with chocolate shavings for an extra chocolatey touch!