Prepare each flavored gelatin separately by dissolving one package in 1 cup boiling water and stirring until fully dissolved. Add 2/3 cup cold water to each, then pour into shallow containers and refrigerate until firm, about 3 to 4 hours.

Once set, cut the flavored gelatins into small cubes and gently combine them in a large bowl. Chill the bowl while you prepare the cream mixture.

In a small bowl, sprinkle the unflavored gelatin over 1/2 cup cold water and let it bloom for 5 minutes.

Warm the bloomed gelatin gently until fully dissolved, then remove from heat.

In a blender, combine the sweetened condensed milk, evaporated milk, heavy cream, vanilla extract, and dissolved unflavored gelatin. Blend until smooth.

Pour the gelatin cubes into a mold or serving dish, then slowly pour the creamy mixture over them, making sure the cubes are evenly distributed.

Refrigerate until completely set, at least 4 hours or overnight.

Unmold if desired, slice, and serve chilled.