In a large bowl, dissolve the red gelatin in 1 cup of boiling water, stirring until completely dissolved. Add 1 cup of cold water and mix well. Pour the mixture evenly into 8 clear cups and refrigerate for about 1 hour or until set.

While the red layer is setting, prepare the white layer. In a small bowl, sprinkle the unflavored gelatin over 1/2 cup of cold water and let it sit for 5 minutes. In a saucepan, heat the remaining 1/2 cup of water until hot but not boiling. Add the softened unflavored gelatin and stir until dissolved. Remove from heat and let cool slightly.

In a medium bowl, whip the heavy cream with the powdered sugar and vanilla extract until soft peaks form. Gently fold the whipped cream into the cooled gelatin mixture until well combined. Carefully spoon the white layer over the set red layer in each cup. Refrigerate for another hour to set.

Once the white layer is set, prepare the blue layer by dissolving the blue gelatin in 1 cup of boiling water. Add 1 cup of cold water and mix well. Carefully pour the blue gelatin over the white layer in each cup. Refrigerate for at least 2 hours or until fully set.

Serve chilled and enjoy your festive treat!