Recipe taken from Rose's Heavenly Cakes by Rose Levy Beranbaum 3 (90g) large egg whites 2 tablespoons red food colouring 1 1/2 teaspoons pure vanilla extract 2 cups (200g) cake flour or plain flour 1 cup (200g) caster sugar 3 teaspoons baking powder 1 teaspoon unsweetened cocoa powder 1/2 teaspoon salt 1/4 cup canola oil 4 tablespoons (57g) unsalted butter 1/2 cup buttermilk Special Equipment One 9 by 2-inch heart-shape or round cake pan (8 to 8²⁄³ cups), encircled with a cake strip, bottom coated with shortening, topped with parchment cut to shape, then coated with baking spray with flour Preheat the Oven Twenty minutes or more before baking, set an oven rack in the lower third of the oven and preheat the oven to 350°F/175°C. Mix the Liquid Ingredients In a medium bowl, whisk the egg whites, red food color, and vanilla just until lightly combined. (Caution: Be careful…