Using egg scissors, remove the narrow point of the eggshells. Make sure to remove any small fragments as you cut. Empty the eggs (you can save the yolks and whites for another recipe or for breakfast the next day). Carefully peel away and discard the inside membrane from the eggshell.
Fill a large saucepan halfway with water and bring to a boil over medium heat. Lay out paper towels on the work surface.
Gently place the empty eggshells into the boiling water and let them simmer for 1 minute. Carefully remove the shells with a slotted spoon. Place the shells hole down on the paper towels to drain out any excess water. Let the shells cool completely.
Lightly coat the inside of the eggshells with cooking oil spray. Rub the spray evenly over the interior of the shells with your finger to make sure the surface is covered. This will help ensure that the marshmallow does not stick to the shell. Reserve the shells in a clean egg carton until ready to fill.*
Make Soft Caramel
Combine the cream, corn syrup and brown sugar in a small saucepan. Bring to a boil over medium heat. Remove from the heat and set aside, keeping it warm.
Place an empty medium saucepan over high heat. When the saucepan is hot, sprinkle a thin, even layer of granulated sugar into the saucepan. As the sugar melts and caramelises, slowly whisk in the rest of the sugar, one small handful at a time, until all the sugar has been added.±
When all of the sugar has caramelised and turned deep amber, slowly stream in one-third of the hot cream, whisking constantly. Be careful! The cream might cause the caramel to splatter. When incorporated, whisk in the next third, and then the last.‡ When all of the cream has been added, turn down the heat to low and continue to whisk the caramel until it reaches 221°F (105°C), 4 to 5 minutes. Remove from the heat, whisk in the fleur de sel, pour into a medium heatproof bowl, and let cool completely.
When the caramel has cooled, stir well to reemulsify any fat that may have separated. Fill a piping bag with the caramel and refrigerate until needed.
Sprinkle the gelatine over the water in a small bowl. Stir and let sit for about 20 minutes to bloom.
Combine the granulated sugar, corn syrup, honey and water in a medium saucepan. Bring to a boil over medium heat. Cook without stirring until the syrup reaches 248°F (120°C).§
Carefully pour the hot syrup into a stand mixer fitted with a whisk and add the bloomed gelatine. Let it cool for 5 minutes, until warm. Then whip on low speed until combined. Increase the speed to medium-high and continue to whip for 4 to 6 minutes. The mixture will turn white and quadruple in volume. When the marshmallow is firm enough to hold a peak, stop whipping.
Cut the tip of a piping bag to snugly fit a #803 plain tip. Using a rubber spatula, place 2 large scoops of marshmallow in the bag so that it is one-third full. Push the marshmallow down toward the tip of the bag. Remove the caramel-filled piping bag from the refrigerator and cut an opening about ½inch (1.25cm) wide straight across the tip of the bag.
1. Working as quickly as possible, assemble the chicks one at a time. While the marshmallow is still warm, pipe it into an eggshell to fill it three-quarters full. Set the piping bag with marshmallow aside. Pipe a cherry-size dollop of the soft caramel into the centre of the marshmallow. Pick up the marshmallow-filled piping bag and fill the eggshell to the brim. Then, holding the tip ¾ to 1inch (2cm) above the egg, pipe a marshmallow teardrop on top, pulling the tip away as you finish. This will form a small beak for the chick.** Immediately sprinkle with yellow sanding sugar to cover all exposed areas of the marshmallow. Continue filling the remaining eggshells one at a time. Refill your piping bag with marshmallow as necessary.±±
Melt a small amount of dark chocolate in the microwave. Mix it gently, making sure it is not too hot. Pour the chocolate into the third piping bag or the baking paper cornet and cut a very small opening across the tip, about the size of the tip of a pen. Pipe 2 small dots onto each chick’s head for ‘eyes’. Let set at room temperature for at least 1 hour before serving.