Chef’s preferred method — Spiced infusion (smooth, nuanced):
Prep: Chop the chocolate into small pieces so it melts evenly. If using a vanilla bean, split and scrape the seeds. Lightly toast whole spices in a dry skillet for 1–2 minutes over medium heat until aromatic (if using whole spices).
Warm & infuse: In a heavy-bottomed saucepan combine the milk and cream with toasted whole spices, the vanilla seeds + pod (or extract), and the cinnamon stick. Heat gently over medium-low, bringing the milk to just below a simmer (tiny bubbles at the edge). Keep at that temperature for 8–12 minutes to allow spices to infuse—do not boil.
Strain: Remove from heat and let rest 3–5 minutes. Strain the spiced milk through a fine mesh sieve into a clean saucepan to remove whole spices and vanilla pod.
Melt chocolate: Return the strained milk to medium-low heat. Add the chopped chocolate and sugar. Whisk continuously until the chocolate is fully melted and the mixture is smooth and glossy (2–4 minutes). Taste and adjust sweetness.
Add chai blend (if using ground spices): Stir in 1½–2 teaspoons of the ground chai blend and a pinch of flaky sea salt; whisk to incorporate. Warm through for 1–2 minutes—do not boil.
Serve: Pour into warmed mugs. Top with whipped cream or frothed milk, a sprinkle of chai spice or cocoa, chocolate shavings, and a cinnamon stick. For an adult version, stir in 1–2 tablespoons of rum, bourbon, or chocolate liqueur per cup.
Quick method — Direct spice blend (fast): Warm milk + vanilla, whisk in 2 teaspoons ground chai blend and sugar, then melt chopped chocolate in the warmed milk and finish as above.