First wash the lemons and drain them.
Cut off the ends.
Cut the lemons in half.
Juice them.
Cover the cup of juice with plastic wrap and refrigerate.
Place the lemon peels in a big pot with about 10 cups water.
Place the pot over medium heat.
Bring to a boil then reduce the heat to medium low and let cook for at least 30 minutes (the longer you cook them, the better).
Add about 4 cups water and add the granulated sugar.
Increase the heat to medium. Bring to a boil.
Let boil for 2 to 3 minutes.
Let cool completely for few hours preferably overnight.
Strain the lemon peels juice.
Add the fresh lemon juice (strained) to the lemon peels juice.
Pour in a cup and enjoy.