Place the water, sugar and sliced strawberries in a saucepan and stir to combine.
Bring to a boil, then reduce to a simmer and cook for about 20 minutes. The strawberries should be very soft and a deep red color.
Remove from heat and strain the strawberries through a fine mesh strainer into a measuring cup or bowl. Resist the urge to press down on the strawberries to release more liquid, doing so will make your strawberry syrup cloudy.
Pour into a glass container, seal, and refrigerate. The syrup should last for several weeks in the refrigerator or you can freeze in a freezer-safe container for two months.
I did not remove the foam that was floating on top, it disappeared by itself in the refrigerator.
For a thicker syrup to use for pancakes, simmer for an additional 10 minutes to thicken the syrup.