First, wash the lemon and cut it in half. Then, squeeze one of the lemon halves into a glass and cut the other half into slices.
Boil 1 liter of water in a pot on the stove with high heat and the lid on.
When the water starts boiling turn off the heat. Now that the water is hot it is time to add all the ingredients: pour the black tea or soak the tea bags, pour the lemon juice, add the lemon slices, add the sugar or honey, and slowly stir for a minute.
Cover the pot and let the beverage rest for 8 - 10 minutes.
After that time, the iced tea has already gained its characteristic flavor and it is ready but still warm. So you have to either strain the tea and let the drink chill in the fridge for at least 1 hour (then it will be ready to serve) or let it rest in the pot with the lid on for at least 4 hours.