For the oats: in a medium bowl, stir together the oats, sugar, yogurt and milk. Scoop into a sealed container and leave to chill in the fridge for at least 4 hours.
For the icing swirl: In a small bowl, stir together the cream cheese, vanilla extract and powdered sugar until smooth. Scoop into a piping bag (if you're feeling fancy) or place inside a sealed container and chill in the fridge.
In the morning, make the cinnamon drizzle by stirring the cinnamon, brown sugar and water together in a tiny bowl. Cook in the microwave for 1 minute until the sugar has dissolved and a syrup forms.
To assemble, scoop the oats into a serving bowl. Drizzle over the cinnamon syrup and then pipe or spread on the cream cheese swirl.