Heat oven to 180 D. Generously spray a cake pan. Set aside.
In a large bowl sift together flour, baking powder, and salt. Set aside. Beat eggs, egg yolk and sugar until mixture is thick and batter falls from whisk in a thick ribbon about 4-5 minutes. Beat in vanilla.
In the meantime, heat milk and butter until just scalding and little bubbles appear around the edge of the pan.
Remove from heat and set aside to cool slightly.
With the mixer off, pour all the flour mixture into the egg mixture. Gently fold until no flour streaks are visible (do not over mix).
Add in milk mixture and fold just until combined. Pour batter into prepared pan.
Bake for 50-60 minutes or until inserted cake tester is free of wet batter. Remove cake from oven and transfer to a wire rack to cool for 25 minutes before turning over to remove cake from pan.