Juice 4-5 grapefruits. Each grapefruit will yield approximately ½ a cup of grapefruit juice.
Sometimes grapefruits will have tiny seeds. That said, use a fine mesh strainer to filter the seeds. If you prefer, you can also remove the pulp. Personally, I like the pulp in this simple syrup recipe.
Measure two cups of grapefruit juice and add it to a one-quart sauce pan. Add two cups of sugar to the juice and cook on medium-high heat for 15 minutes or until the sugar has full dissolved.
Once the sugar has fully dissolved, remove from the heat source. Cool the simple syrup and store in a Mason Jar. Once cooled, you are ready to use the syrup in cocktails, spritzers and more!