Combine rhubarb with orange juice, sugar and cinnamon. Cook gently (stirring often) until rhubarb is softened.
Cut poached pears into small chunks and combine with cooked rhubarb.
Using an immersion blender, blend until smooth. Add heavy cream slowly and stir until creamy.
Adjust sugar and cinnamon if needed.
Chill. Serve with slice of orange and sprig of fresh mint.