Pre-heat oven to 350 degrees.
Lightly coat a 13x9" rimmed baking sheet with cooking spray, line with parchment paper, and then coat parchment with more cooking spray.
Put 6-8 strawberries in blender and blend until puréed. You'll want to have ⅓ cup.
In the bowl of a stand mixer, beat egg whites and cream of tater on medium-high speed until stiff peaks form.
In a separate large bowl, sift together sugar, flour, and salt.
Gently fold sugar mixture into egg whites, about ½ cup at a time, incorporating well but taking care not to over-mix.
Fold in vanilla extract and strawberry purée.
Spread batter evenly into prepared baking pan and bake at 350 degrees until cake is set and starting to turn golden on top, about 25-30 minutes.
Let cake cool completely in pan before removing, slicing, and frosting.