Bring 4 cups of water to a boil in a large pot.
Add the tapioca pearls to the boiling water and stir gently to prevent sticking.
Cook the pearls according to the package instructions, typically about 5-7 minutes for quick-cooking pearls, or 20-30 minutes for traditional pearls, until they are soft and chewy.
Once cooked, drain the pearls and rinse them under cold water.
If desired, soak the cooked pearls in a mixture of 1/2 cup brown sugar and 1/2 cup water to sweeten them. Let them sit for at least 10 minutes to absorb the sweetness.
In a separate pot, bring 4 cups of water to a boil.
Add the black tea bags or loose tea leaves to the boiling water and steep for 5-7 minutes, or until the tea is strong.
Remove the tea bags or strain the tea leaves.
Stir in the sugar while the tea is still hot, adjusting the amount to taste. Allow the tea to cool to room temperature, then refrigerate until cold.
Divide the cooked tapioca pearls among the serving glasses.
Add ice cubes to each glass.
Pour the sweetened black tea over the ice and pearls, filling each glass about three-quarters full.
Top off each glass with milk or non-dairy milk, adjusting the amount to your preference.
Stir the bubble tea to mix the ingredients.
Enjoy your meal!