Cook the tapioca pearls according to the directions on the package. Drain and soak in cold water.
Make the milk tea
Boil the water in a large pot and add all of the black tea bags. Boil for about 5 minutes. Remove from the heat and add the sweetened condensed milk, adding a little at a time until you achieve the sweetness that you want. Set aside and allow to cool.
Assemble bubble tea
Put the tapioca pearls in a tall glass and add the milk tea. You can also add ice if you like. Serve with a large straw. Enjoy!