2 c. water
1 c. light corn syrup
1/2 c. sugar
2/3 c. lemon juice

In heavy, medium sized saucepan, stir together water, corn syrup and sugar. Heat to boiling over medium high heat. Reduce heat to low and simmer, uncovered, 5 minutes. Remove from heat; cool for 30 minutes. Stir in lemon juice. Pour into 9 inch square baking pan. Cover surface with plastic wrap. Freeze 3 to 4 hours, or until frozen but still soft in center. Spoon into blender container; cover. Blend on high speed until mixture becomes white and creamy. Turn back into 9 inch square pan. Cover with plastic wrap. Freeze mixture about 3 hours or until firm.