In the bowl of a stand mixer fitted with the paddle attachment, beat butter, brown sugar, and vanilla at medium-high speed until light in color and creamy, 1 to 2 minutes.
In a medium bowl, whisk together flour, salt, and cinnamon. With mixer on low speed, gradually add flour mixture to butter mixture, beating just until combined. Use immediately.
Recipe by Bake from Scratch at https://staging.bakefromscratch.com/strawberry-pie-bars/