First, rinse your quinoa really well.
I use a fine mess strainer to do this. Giving quinoa a good rinse before cooking can help to remove that sometimes slightly bitter flavor it can take on.
In a small to medium pot, heat the milk and salt until very hot, almost boiling. Stir in the quinoa and cinnamon, then cover the pot with a lid and reduce the heat to a simmer.
Cook for 12-15 minutes (see notes) until most of the liquid has been absorbed into the grains, although it may still look a little soupy (that’s OK for now!)
Keep cooking for another 5 minutes until the majority of the liquid is gone and the quinoa is well cooked, but will seem like porridge (in part from the added, mashed banana). Remove from the heat and divide into two bowls.
Top with sliced fruit, nuts, or seeds.