Bring 2 cups of filtered water to a gentle boil in a small saucepan or kettle.
Add the loose-leaf tea (or tea bag) and fresh ginger slices.
Steep for 5–7 minutes, allowing flavors to infuse.
Stir in ground cinnamon (or add cinnamon stick) and mix well.
Strain the tea into mugs.
Squeeze in the juice of ½ lemon just before serving for maximum vitamin C.
Serve hot or allow to cool and pour over ice for an iced version.