Toast 3 whole cloves, 2 green cardamom pods, 1 cinnamon stick, and 3 to 4 black peppercorns in a small saucepan over medium heat for 1 to 2 minutes.

Add 1 cup water and 1 inch sliced fresh ginger to the saucepan and bring to a simmer.

Reduce heat to low and simmer the spices and ginger for 5 minutes.

Remove the saucepan from heat, add 2 tea bags or 2 teaspoons loose black tea, and steep for 3 to 4 minutes.

Strain the chai concentrate through a fine mesh strainer into a container, discarding solids.

While warm, stir in 2 to 3 tablespoons sweetener until fully dissolved.

Let the chai concentrate cool to room temperature (about 5 minutes) or chill in the refrigerator for 3 to 4 minutes.

Fill tall glasses with 1 cup of ice cubes each.

Pour about 1/2 cup of cooled chai concentrate into each glass.

Slowly pour 1 cup cold milk or milk alternative into each glass and stir gently to combine.