In a small saucepan, combine fresh orange juice and sugar over medium heat. Stir gently as the mixture warms for about 3-5 minutes until the sugar dissolves.

Once hot, sprinkle unflavored gelatin over the surface and stir until fully dissolved, about 2-3 minutes.

Carefully pour the orange mixture into molds or jars, filling halfway. Allow to cool for 30 minutes at room temperature.

In another saucepan, gently warm the heavy cream over low heat for 2-3 minutes, then stir in vanilla extract and sugar. Sprinkle gelatin over warm cream and mix until dissolved.

Once the orange jelly has set for at least 2 hours, pour the vanilla cream layer over it. Chill for an additional 2 hours.

Once set, serve chilled, optionally topped with whipped cream and a slice of orange.