Preheat oven to 350°F (180°C). Spray a 13×9-inch baking pan with baking spray with flour. Line pan with parchment paper, letting excess extend over sides of pan.

In the bowl of a stand mixer fitted with the paddle attachment, beat butter and brown sugar at medium-high speed until creamy, 3 to 4 minutes, stopping to scrape sides of bowl. Add egg, beating until combined. Add flour, salt, and vanilla, beating until a dough forms. Firmly press three-fourths of dough (555 grams) into bottom of prepared pan.

Bake until edges are light golden brown, about 15 minutes. Let cool completely in pan. Leave oven on.

Line a rimmed baking sheet with parchment paper. Crumble remaining dough onto prepared pan.

Bake until golden brown, 8 to 10 minutes. Let cool completely.

Clean bowl of stand mixer and paddle attachment. Using the paddle attachment, beat cream cheese at medium-high speed until smooth. Reduce mixer speed to medium-low, and add confectioners’ sugar, ¼ cup (30 grams) at a time, beating until combined after each addition. Transfer to a large bowl, and set aside.

Clean bowl of stand mixer. Using the whisk attachment, beat cream at medium-high speed until medium-stiff peaks form. Using a balloon whisk, fold whipped cream into cream cheese mixture in two additions. Fold in chopped strawberries, and spread in an even layer on top of cooled crust.

Crush shortbread crumbles into smaller pieces, if necessary. Sprinkle evenly on top of filling. Sprinkle with freeze-dried strawberries, and refrigerate, uncovered, for 2 hours or up to overnight.

Using excess parchment as handles, remove from pan, and cut into bars. Store in an airtight container for up to 3 days.