Heat the sugar and water in a saucepan over medium heat. Stir to dissolve the sugar.
When the sugar solution begins to boil, pour in the lemon juice through a fine meshed strainer, and stir. Immediately turn the heat down to low.
Keep the lid off of the saucepan, set the timer for 60 minutes and let it simmer at low heat. Do NOT stir. The solution will first appear clear, slowly turn pale yellow, and end up a golden/amber color after 60 minutes. After 60 minutes have elapsed, the liquid might look a bit thin. However, it will thicken to the consistency of honey once it cools.
Pour the warm syrup into a heatproof container, and let it cool completely before sealing and storing. It will keep for at least a year, as long as you always use clean utensils when handling!
Can be stored at room temperature for up to 1 year.