In a medium saucepan, bring 1 cup of water to a boil. Add the tapioca pearls and cook according to the package instructions, usually about 15-20 minutes, until fully translucent and chewy.
Once cooked, drain the boba and rinse under cold water to stop the cooking process. Sweeten the boba by soaking them in a small amount of sweetened condensed milk or sugar syrup. Set aside.
Steep the Thai tea mix or tea bags in 1 cup of boiling water for about 5 minutes or according to the tea strength preference. Remove the tea mix or bags and allow the tea to cool to room temperature. You can place it in the refrigerator to cool faster.
Fill a serving glass about halfway with ice cubes. Add the sweetened boba pearls to the bottom of the glass.
Pour the cooled Thai tea over the ice and boba.
Top off with sweetened condensed milk and evaporated milk or coconut milk, adjusting the amounts based on your preference for sweetness and creaminess.