Add all the ingredients to a high-speed blender. Blend until smooth and creamy.
Taste. Add more sweetener or a little more lemon zest for brightness if needed.
Pour into the jars and refrigerate for at least 4 hours (or overnight) until thickened.
When ready to enjoy, give it a good stir and add blueberries on top (optional).
Store chia pudding in the fridge for up to 5 days.