Preheat oven to 325 degrees and grease a 9x13-inch baking pan.
In a large bowl, whisk together cake mix, flour, sugar, and salt.
Add water, buttermilk, sour cream, egg whites, vanilla extract, and almond extract.Use an electric mixer to mix at medium-low speed until evenly mixed.
Pour batter into prepared pan. Bake for 26 to 30 minutes. Let cool.
To make icing, in a large bowl beat cream cheese and butter until smooth and creamy.
Add the extracts, powdered sugar and milk. Beat at medium speed until combined. Beat at high speed for 1 minute.
Spread icing on cake. Decorate with sprinkles if desired.