In the stove-top pot, bring the water to a boil. Add in the Thai tea leaves and stir them down until all the leaves are submerged.
Cover the lid and adjust the heat to low, until the mixture is simmering. Simmer for 5 minutes.
While the tea is simmering, add condensed milk into a heat-proof cup.
Strain the tea mixer into the heat-proof cup with condensed milk and stir until well combined.
Let the mixture sit for 10min to cool down (best to make a several servings at once and let it cool down in the fridge before adding ice)
In your serving glass, add in the ice. Gently pour over the prepared Thai tea.
Stir well and enjoy!