Blend the avocado and banana with a little of the milk.
When smooth, add some more milk, the cacao, orange juice, zest and honey and blend again until fully combined.
Add the chia seeds, bearing in mind these will swell and absorb a lot of the liquid so not too many.
Transfer into serving pots and place in the fridge until ready to eat. Leave for at least 15 minutes to give the chia chance to swell and for anywhere up to a day or 2.
I served mine with some chopped dried fig and slices of clementine. Mint or nuts or seeds would also work well.