In a medium sized pot, combine strawberries, sugar, lemon zest and lemon juice. Heat over medium-low and simmer for 5 minutes.
Using an immersion blender, blend the strawberry mixture until smooth. At this point, you can transfer the sauce into a mason jar to cool. Or if you wanted to remove the seeds from the sauce, run the sauce through a seive.
Allow the sauce to cool completely before storing it in an airtight container in the fridge. Good for up to 1 week!
Enjoy with your favorite ice cream, milk, or with my strawberry cream donut recipe! (see note)