Chai tea is my favorite too. I usually drink it in colder weather and I make my own. I still like Starbucks or Paneras chai, but after making my own, they really don't compare.
It takes fresh ginger: 5 quarter sized slices unpeeled, 10 crushed green cardamom pods, 10 black peppercorns, 2-3 inches stick cinnamon, 10 whole cloves in 3 cups of water, bring to boil, simmer 10 minutes, put in 1 tablespoon black tea, bring to boil, simmer three minutes, put in 1 cup milk and heat, add sweetener if needed, I use brown sugar. Strain and serve.
I sometimes foam up nonfat milk and and do half that and half chai in a cup.
Different spices can be used, fennel, star anise, allspice, to name a few. There are lots of chai recipes on the internet with variations.