Add milk, oats, chia seeds, sweetener, vanilla, and salt to a medium mixing bowl.
Whisk or stir very well, making sure there are no clumps of chia seeds.
Allow the mixture to rest for a few minutes, then stir once more. This step ensures the chia begins to gel evenly.
Transfer into airtight jars or containers.
Refrigerate for a minimum of 4 hours or overnight for best results.
Once set, open the jars and give it a quick stir before serving.
Add fresh fruit, nuts, seeds, or nut butter just before eating.