Wash and dry the lemons. Using a very sharp knife, slice them as thin as possible, removing the seeds as you go. If you have a mandolin, this will get your slices very thin and even.
In a wide pot or deep, wide pan, add the water and the sugar. Stirring frequently, bring to a boil. Once all the sugar has dissolved, reduce heat to low and simmer. Add the lemon slices and keep the spread out in the simple syrup.
Simmer the lemon slices for about an hour, unil the rind and pith start to turn translucent. Once translucent, remove them from the syrup onto a parchment lined sheet pan
You can air dry the lemons for about 24-48 hours, flipping them over halfway through but they will still remain sticky to the touch. Another option is to set your oven as low as possible and let the lemons dry in the oven, which will result in less sticky candied lemons. Check them and flip them frequently so they don’t burn. If they begin to get dark or turn brown, remove them from the oven. They will require a good 1-2 hours in the oven to fully dry.
Once finished, you can use your candied lemons as a garnish for desserts, or simply eat them plain. The syrup may be saved and used to flavor drinks, or discarded.