In a large pot, bring 4 cups of water to a boil.
Add the loose black tea leaves or tea bags to the boiling water.
Reduce the heat and let the tea simmer for about 5 minutes.
If using tea bags, remove them after 5 minutes.
Strain the tea to remove the loose leaves, pouring the tea back into the pot.
Add the salt to the tea and stir well to dissolve.
Add the unsalted butter to the pot.
Using a churner or an immersion blender, blend the tea and butter mixture until it is frothy and the butter is fully incorporated.
If you prefer a creamier texture, add the milk to the pot and heat gently, stirring to combine.
Pour the Suja into cups or bowls.
Enjoy your meal!