If you don't want to squeeze your own grapefruit juice, you can use juice from the carton or a bottled grapefruit juice.
Combine water and sweetener in a saucepan; bring to a boil. Add orange rind; reduce heat, and simmer 5 minutes. Strain mixture, discarding rind. Cool completely.
Add grapefruit juice and lemon juice to water mixture; stir well. Pour into a 9-inch square baking pan; cover and freeze until firm.
Break frozen mixture into pieces. Add frozen mixture to a blender or food processor, in batches, and process until smooth but not thawed. Serve immediately.
carbo rating: 6
The Complete Step-by-Step Low Carb Cookbook
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