Make Homemade Marshmallow Eggs: pipe pillowy marshmallows, coat in dark chocolate, and decorate for a cheerful treat.
Lightly dust two rimmed baking sheets with a generous layer of confectioners' sugar and use a single whole egg (shell intact) pressed gently into the sugar to create a shallow, egg-shaped indentation in repeating rows; tap out the egg and repeat to stamp a dozen-or-more smooth, pillowed cavities. Keep a small bowl of extra confectioners' sugar nearby for dusting. Arrange the prepared sheets on the painted pine wood surface and set them aside to catch the piped marshmallow later.
Combine the three packages of unflavored gelatin with ½ cup (118g) cold water in the metal bowl of a stand mixer fitted with the whisk attachment. Let the gelatin sit undisturbed until it swells and becomes glossy and slightly spongy — the powder will absorb the water and form a soft, translucent bloom that will melt seamlessly into the sugar syrup.
In a clean saucepan bring granulated sugar, light corn syrup and ½ cup (118g) water together and heat until the sugar fully dissolves and the syrup reaches the soft-ball stage (about 240°F) — the syrup will become viscous and amber-tinged with a smooth, glossy surface. Remove from heat and let the very hot syrup rest briefly so it’s ready to be poured safely into the bloomed gelatin.
With the stand mixer running on low, pour the hot syrup in a steady stream into the bloomed gelatin, then increase speed and whisk on high for about 10 minutes until the mixture transforms into a voluminous, cloud-like marshmallow: glossy, ribboning off the whisk, dense but airy, with stiff peaks that hold their shape and a satiny sheen.
Transfer the marshmallow into a pastry bag fitted with a round tip and pipe plump, rounded eggs into each confectioners-sugar-lined indentation on the baking sheets. Dust any sticky tops lightly with confectioners' sugar and allow the piped marshmallow eggs to rest and set for 1–2 hours until they are springy to the touch and hold their molded shape.

Roughly chop the 70% dark chocolate and melt it gently in a heatproof bowl in short increments, stirring to a smooth, glossy pourable ganache-like fluid. Dust each marshmallow egg to remove excess confectioners' sugar, then drop one in at a time and lift with a fork to let the excess chocolate run off before placing them onto a parchment-lined sheet. If using sprinkles, add them while the chocolate is still wet so they adhere to the glossy surface.
Warm candy melts and transfer to a small piping bag or squeeze bottle to drizzle fine lines, spirals, dots, and playful patterns in bright pinks, blues, greens and yellows across the hardened dark chocolate shells. Arrange the finished eggs nestled in white paper liners inside a green speckled tray for serving; store at room temperature up to 24 hours or refrigerate for up to a week.
