Stir the grated lemon zest into the lemon juice. Set aside.
Sprinkle the gelatin over the cold water and set aside to soften.
Start whipping the egg yolks at medium speed on a mixer. Place the corn syrup in a small saucepan and bring to a boil. Lower the mixer speed and pour the hot syrup into the whipped egg yolks in a thin, steady stream. Increase t