Measure water into a wide saucepan.
Add the sugar. Place the saucepan over low heat and stir the sugar to dissolve.
Once the sugar is dissolved, add the lemon slices into the syrup. Place them in a single layer and avoid placing them on top of each other.
Let the lemon slices cook in the syrup over low heat. Turn the slices over every 20 minutes.
Continue to cook the slices over low heat until the sugar syrup starts to turn amber.
As soon as it reaches the desired color, remove the lemon slices onto a parchment lined tray. Place them apart to avoid sticking.
Let the caramelized lemon slices dry and set overnight, uncovered.
To store the slices, place a small parchment square in between each lemon slice to avoid the slices from sticking. Keep refridgerated until ready to use.