Heat oven to 350°F. With butter, grease two 8-inch cake pans and cover the bottoms with parchment paper. Grease the paper too, and lightly dust both pans with flour.
Sift flour, baking powder, sugar and salt in bowl of stand mixer. With paddle attachment, blend on slow for 10 seconds.
In small bowl lightly whisk eggs with ¼ cup of the milk and vanilla extract; set aside.
To the dry mixture, add the butter and beat on low for about a minute until combined. Slowly add the remaining ½ cup milk until incorporated into dry ingredients.
Increase speed to medium and blend for about a minute until the batter is thick and smooth.
Add egg/milk mixture in three parts on medium speed, scraping down sides and bottom at least once. Beat for another 30 seconds until batter looks a bit airy and smooth.
Color Layers:
Pour half the batter into another mixing bowl. To one bowl, fold in about 5 drops of red food coloring and to the other fold in about 5 drops of blue food coloring. Make sure color looks even in both bowls. Pour blue batter into one of the baking pans and the red into the other.
Bake for about 25 minutes, until light golden brown and toothpicks come out dry when inserted in the top center. Remove pans, let cool in pan for 10 minutes, and then on wire rack until room temperature.
Whipped Cream Topping:
On high speed, beat whipping cream with confectioners' sugar and vanilla extract until stiff peaks form.
Prepare Cake:
With serrated knife, trim edges of cake.
With spatula, spread 1/3 of whipped topping onto first layer of cake. Add second cake layer.
Spread the remainder of the whipped cream to the top of the cake and arrange berries in any pattern.
Notes
Nutrition information calculated based on a 16 slice yield.