Wash the spearmint leaves in cold water and dry them with a paper towel. Discard any yellow or spotted leaves. Separate the leaves and stems, and place the leaves in a pot.
Fill a kettle with hot water and place on medium to high heat on a stove. When the kettle whistles, pour the boiling water over the spearmint leaves in the pot. Use enough water to just cover the leaves. Gently press down on the leaves with a long spoon. Steep the tea by covering it and leaving it on the stove for 10 to 30 minutes.
Strain the tea using a colander or strainer while you pour it into your tea cup. Allow it to cool and drink it as you would any other tea. Or, pour the tea over ice or store it in the refrigerator for iced tea.