Mix 1/2 cup sugar and strawberries. Add the lemon zest and juice. Cover and let sit overnight in the refrigerator.
Pour mixture into large saucepan. Make sure you have 3 or four inches of bare pot exposed to prevent the mixture from spilling over. Add salt and another 1/2 cup sugar. Bring to a fast boil taking care the bottom doesn't scorch. Maintain a nice boil while skimming surface a few times. Simmer 20 minutes or until candy thermometer reaches 220 degrees. Cool the mixture. Store in the refrigerator.
Check out Rebekah's desserts at City House, in the heart of Germantown.