Preheat the oven to 350F (160C) degrees.
Line the bottom of two 8-inch cake pans with rounds of parchment paper. Grease and flour the sides.
In a large bowl, sift together the flour, baking powder, baking soda and salt. Give the bowl a whisk.
In a separate large bowl, beat the butter and sugar until fluffy (about 1-2 minutes). Beat in the oil.
Beat in the egg whites 1 at a time, turning off the mixer and scraping down the sides of the bowl as necessary. Mix in the sour cream.
In a large measuring cup or medium bowl, whisk together the milk, lemon juice, reduced strawberry puree and optional food coloring.
With the mixer on low speed, beat about ⅓ of the flour mixture into the butter mixture. Then mix in about ⅓ of the milk and strawberry mixture. Turn off the mixer and scrape down the sides of the bowl. Repeat the process until all the flour mixture and milk mixture are incorporated. Do not over mix the batter.
Divide the batter evenly between the 2 pans and smooth the top.
Bake in the preheated oven for 30-35 minutes, or until an inserted toothpick comes out clean or with a few cake crumbs.
Cool the cakes completely in the pan, then gently inserted onto a wire rack.