While Kashmiri chai is a green tea, it’s actually pink in colour.
Originally a Himalayan drink, pink tea goes by many names across South Asia, some which reference its unusual color and flavor, from nun chai (salt tea) to gulabi chai (rose-hued tea). Salt and baking soda are key ingredients. Salt acts as an electrolyte to prevent dehydration at high altitudes, and baking soda is the catalyst that turns it pink. Infused with spices such as star anise and topped with crushed nuts, the tea is tailor-made for cold weather. In Kashmir, nun chai is drunk piping hot several times a day, accompanied by an array of breads: crispy kulcha, dimpled girda, or bagel-like tsochwor.
via Atlas Obscura
There are plenty of recipes online (some more authentic, some quicker and easier) but the key to its pinkness is getting in the right reaction between the baking soda and your green tea leaves and how long you brew it for.