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Pour the gelatin mixture into three separate bowls. Each bowl should contain the same amount of the mixture. By dividing the mixture, you can color each one a different shade of green to make the tri-colored jello shots. When all three layers have been poured, transfer the shots to the refrigerator one last time. Let the jello set overnight if possible, or for at least four hours. The jello is ready when it's completely firm. To prevent a hard film from developing on top of the jello, cover the shots with a large sheet of plastic wrap. Right before it's time to serve the jello shots, remove them from the refrigerator. Top each one with a small dollop of whipped cream to fill the remaining quarter of the shot glasses. You can also garnish them with green or gold sugar if you like. Serve the shots with small spoons so people can dig out the jello.
Divide the mixture. Give the jello time to set. Garnish with whipped cream before serving.