Thinly slice lemon. Blanch in 2 cups boiling water for 5 minutes; drain. In the same saucepan, stir together 1 cup water and 1 1/2 cups sugar; stir to dissolve sugar. Add blanched lemon slices and heat until the mixture starts to boil slightly. Reduce to simmer; simmer uncovered for 1 hour. Remove from heat.
Spray a cooling rack with non-stick spray and place individual lemon slices in a single layer to dry for up to 24 hours. Store in an airtight container separated with wax paper.
Note - the lemon infused sugar syrup can be used to make sorbet, ice tea, etc.