Preheat oven to 350 degrees. Prepare three 8" cake pans with pam and parchment.
In a medium bowl combine and stir the egg whites, 1/4 cup of milk, and the vanilla. Set aside.
In the bowl of an electric mixer fitted with the paddle attachment, combine the dry ingredients together on low speed for 30 seconds.
Add the butter and remaining milk, and mix on a low speed until just combined. Increase to medium speed and mix for 1-2 minutes.
Scrape the sides of the bowl and begin to add the egg mixture in 2 separate batches, beat on medium speed until it is just combined.
With a rubber spatula, fold lemon juice, lemon zest and a few drops of yellow food coloring. The batter should be a bright yellow color.
Divide the batter between the three cake pans.
Bake for about 25 minutes or until a toothpick comes out clean.
Let cool on racks until cooled completely.