Bloom gelatin in cold water. In a small mixing bowl, pour water and then sprinkle a single layer of gelatin over the surface. Avoid creating any mounds as this can hinder the crystals from dissolving properly. Allow the mixture to sit for 5 to 10 minutes to soften.
Heat cream, sugar, green gel food coloring, and mint extract in a saucepan on medium heat. Heat the mixture just until it comes to a boil and the sugar dissolves. Remove the pan from heat.
Add the gelatin to the saucepan and whisk immediately until it is smooth and fully dissolved. If the gelatin hasn't fully dissolved, return the pan to low heat and gently heat while stirring constantly. Make sure not to let the mixture boil.
Pour the mixture into the liners, filling to the top.
Refrigerate for a few hours.