Iced Chai

Coarsely crush cardamom pods with a mortar and pestle, then partially grind seeds. Transfer to a plate. Grind peppercorns with mortar and pestle until about medium-coarse; transfer to same plate.

Rinse a medium pot (about 9" diameter) with water (this helps keep the milk from scorching). Combine milk, cardamom pods and seeds, pepper, and ginger in pot and bring to a rolling boil over medium heat, scraping sides and bottom of pot occasionally with a heatproof rubber spatula. When foam starts to rise, cook 20 seconds, scraping spices from sides of pot (some plant-based milks won’t foam; simply cook 30 seconds from boiling). Reduce heat to low to allow foam to die down, then increase heat to medium-low and simmer, scraping bottom and sides of pot occasionally and adjusting heat as need to keep foam from rising, until milk is light tan in color from spices, about 2 minutes.

Stir in tea and simmer, scraping pot occasionally and adjusting heat as needed, until milk is deep tan and reduced by one third, about 4 minutes. Strain through a fine-mesh sieve into a large measuring glass, pressing on solids with spatula. (Soak pot in hot water immediately to help with cleaning.) You should have 2 cups chai concentrate; return chai to pot and simmer another minute to reduce further if needed. Add sugar and stir until dissolved.

Place ice in a large heatproof bowl with a spout or a large heatproof pitcher. Immediately pour hot chai over ice. Stir until ice is almost completely melted (larger cubes may take longer), about 2 minutes. Taste chai and add up to 2 Tbsp. cold water or 1 Tbsp. simple syrup (dissolve 2–4 tsp. sugar in 2 tsp. warm water) if needed. Serve in glasses filled with fresh ice if desired.

Do ahead: Chai can be made 3 days ahead. Transfer to an airtight container; cover and chill.