Place the strawberries and water in a small skillet over medium-low heat and cook, stirring and mashing the whole time, until the strawberries break down into a thick, reduced paste. Transfer to a bowl and let cool completely.

On a stand mixer fitted with a whisk attachment or with a handheld electric mixer, whisk the butter on medium-high for 3-5 minutes, until very fluffy.

Reduce the speed to low and gradually add the powdered sugar until mixed.

Add the strawberries along with the lemon juice and whisk until combined.

Use immediately or cover and refrigerate until ready to use. Bring to room temperature on the counter and re-whip before using.

Store leftover frosting in the refrigerator for up to 2 days.