In a large bowl, combine 2 cups of rolled oats with 2 tablespoons of chia seeds.
Add 1 cup of yogurt and 3 tablespoons of cocoa powder to the mixture in the bowl.
Pour in 3 cups of full cream milk (Dutch Lady) and mix until well combined.
Stir the mixture thoroughly until all ingredients are evenly distributed.
Cover the bowl with a lid or plastic wrap and refrigerate overnight for at least 8 hours.