This is a classic recipe that really IS the perfect pound cake! There is something about this exact mix of these simple pantry staple ingredients that results in a velvety smooth and perfectly dense and tender cake.
Preheat the oven to 350 degrees Fahrenheit and grease a 9x5 loaf pan with pan spray, I find the best to be a baking spray with flour in it. Set aside.
In a large bowl beat the butter with a paddle attachment or a hand mixer until smooth and creamy. Add the sugar and beat for about 2-3 minutes, until light and fluffy.
Add the eggs, egg yolk, vanilla, and salt. Beat on low speed until just combined.
Add the flour and baking powder and mix on medium-low until combined. Scrape down the sides and bottom of the bowl and beat for another minute.
Pour the batter into the prepared pan. Bake for 1 hour and fifteen minutes, until a toothpick comes out nearly clean of crumbs. Be careful not to open the oven too early, or the cake can fall in the middle.
Let the cake cool for 15-20 minutes before turning out of the pan and letting it finish cooling on a cooling rack. Let cool completely before serving.