In a small saucepan, add 2 cups water, sliced ginger, crushed cardamom pods, cloves, peppercorns, cinnamon stick, and star anise (if using). Bring to a gentle boil over medium-high heat.

Simmer to infuse

Once boiling, reduce heat to low and simmer uncovered for 8 minutes to extract and meld the spice flavors.

Add tea leaves and milk

Add the black tea leaves and 1 cup whole milk to the saucepan. Increase heat slightly until the mixture just reaches a gentle simmer (do not boil vigorously), then reduce heat.

Steep

Keep the mixture at a low simmer for 3–4 minutes to allow the tea to steep and the milk to take on the spice color and aroma.

Sweeten and finish

Stir in the brown sugar (or honey, if using) and vanilla extract, if desired. Taste and adjust sweetness. If using freshly grated nutmeg, stir it in now.

Strain

Remove from heat and strain the chai concentrate through a fine mesh sieve or cheesecloth into a heatproof container to remove solids. Press gently on solids with the back of a spoon to extract liquid. Discard solids.

Assemble & Serve (makes one 12 oz latte)

Measure: For a 12 oz serving, use about 1 cup (8 fl oz) of the prepared chai concentrate and 4 fl oz (1/2 cup) additional steamed milk. If you prefer a milder chai flavor, use 3/4 cup concentrate and 1/2–1/4 cup milk to taste.

Heat and froth milk: Warm 4 fl oz (1/2 cup) of whole milk until steaming (around 150–160°F / 65–70°C). Froth with a milk frother, whisk, or by shaking in a sealed jar until foamy.

Combine: Pour 1 cup (8 fl oz) of the strained chai concentrate into a 12 oz cup. Add the steamed/frothed milk on top, holding back foam with a spoon, then spoon foam over the top.

Garnish and serve: Lightly dust with ground cinnamon. Serve immediately.