Place the matcha powder in a small bowl and pour hot water over it. Whisk vigorously with a small whisk until the mixture is smooth, slightly foamy, and no lumps remain, about 30 seconds.
Add honey or maple syrup to the warm matcha paste and whisk again to incorporate, adjusting sweetness to taste.
Fill a tall glass with ice cubes, creating a chilled foundation for your latte.
Pour the cold milk or milk alternative over the ice, filling the glass about three-quarters full, and gently swirl to chill evenly.
Slowly pour the whisked matcha mixture over the milk and ice, allowing it to settle and create a layered look. Watch for the vibrant green to gently swirl into the milk as you pour.
Gently stir or swirl the drink to blend the layers slightly, ensuring the froth is evenly distributed and the drink is beautifully vibrant and inviting.
Serve immediately with a straw or a spoon, enjoying the refreshing, frothy texture and bright green color of your iced matcha latte.