Squeeze the juice from the lemons and put them in the refrigerator, after removing any seeds that may have gotten into the juice.
Cut lemon peels into random pieces, put them in a saucepan, pour water and put on the fire. After boiling, add sugar, stir and cook the broth for 3 minutes. Remove from heat and let it brew for at least 2.5 hours.
Strain the decoction, combine it with the juice squeezed out in advance. Use it chilled or warmed.