Brew 60 ml of espresso. If you use a moka pot or other brewer, make the coffee stronger than usual. Aim for a dark, rich shot so the flavor does not disappear once you add milk and ice.
Let the hot espresso sit at room temperature for 3 to 5 minutes. You want it warm, not boiling. This protects the ice from melting too fast and keeps the drink from tasting watered down.
Prepare your glass. Fill it almost to the top with clean ice cubes. Use solid cubes, not crushed ice, so the drink dilutes more slowly. If you like a very cold drink, chill the empty glass in the fridge for 10 minutes before adding the ice.
Pour the slightly cooled espresso directly over the ice. If you use flavored syrup, add it now. Stir the coffee, ice, and syrup together for a few seconds so the flavor spreads evenly through the drink.
Measure 150 to 200 ml of cold milk in a jug. Start with 150 ml for a stronger coffee taste. Use 200 ml if you prefer a milder and creamier drink. If you want a foam layer, froth a small part of the milk and keep it aside for topping.
Slowly pour the cold milk into the glass over the espresso and ice. As you pour, you will see a layered effect that turns uniform as the liquids mix. Leave a small gap at the top of the glass so you can stir and add toppings.
Taste the latte before adding extra sugar. Many flavored syrups are already sweet. Add your chosen sweetener in small amounts, stir well, then taste again. This helps you avoid an overly sweet drink.
If you frothed some milk earlier, spoon the foam over the surface. You can also add a spoon of whipped cream. Lightly dust the top with cocoa powder or cinnamon for extra aroma and flavor.
Serve the iced latte immediately while it is very cold. Give it a quick stir before each sip if it has been sitting for a while so the coffee and milk stay mixed.