Originally from our friend Rupal, who was born and raised in India, we've been modifying and experimenting with this recipe for the last few years to reach this Truewerk blend and method.
We recommend making the concentrate first and then adding the milk when you're ready to drink the tea. Often we'll triple or more the concentrate recipe and then mix it 50/50 with milk each day before heading to work. The concentrate keeps for at least a week in the fridge without issue.
We strongly recommend sticking with WaghBakri brand tea leaves. The tea marsalas ("marsala", which roughly means 'spice' in Hindi, refers generally to any blend of spices used for cooking Indian cuisine) vary by brand - the Badshah-Kamal brand is our favorite due to its spicy / gingery / peppery blend which gives the chai a vibrant kick. You'll find plenty of selection at your local Indian grocer or online at the links we've provided.
Great iced in the summer months as well.