Boil water in a kettle or a saucepan. Once the water reaches a boil, let it cool for about 3 minutes. This will prevent the green tea from becoming too bitter.
Add the green tea bags or loose-leaf tea to a heat-resistant pitcher.
Pour the hot water over the tea bags or loose-leaf tea. Let the tea steep for 3-5 minutes, depending on your desired strength.
Remove the tea bags or strain the loose-leaf tea. Add the little sweetener of your choice and stir until dissolved.
Allow the hot-brewed tea to cool at room temperature for about 30 minutes.
Add fresh mint leaves and/or lemon juice to enhance the taste of the tea, if desired.
Once the tea has cooled, transfer the pitcher to the refrigerator and chill for at least 2 hours.
Serve the cold drink over ice and garnish with additional mint leaves or lemon wedges, if desired.