In a medium saucepan, combine the chopped strawberries, sugar, water, and lemon juice.

Stir the ingredients together and place the saucepan over medium heat.

Bring the mixture to a boil, then reduce the heat to low and let it simmer for 15 minutes, stirring occasionally.

Remove the saucepan from heat and add vanilla extract (if desired).

Using an immersion blender, blend the syrup until it is smooth and there are no chunks.

Let the syrup cool to room temperature before storing it in an airtight container in the refrigerator for up to 1 month.