1-Preheat the oven: Preheat the oven to 325°F (163°C) and grease a 13×9 inch glass pan.

2-Whisk dry ingredients: In a large bowl, whisk together the flour, sugar, salt, baking powder, and baking soda.

3-Whisk wet ingredients: In another bowl, whisk the buttermilk, whole eggs, egg yolk, vanilla extract, and vegetable oil.

4-Mix the Batter: Cut the room temperature butter into pieces and gradually mix into the dry ingredients on medium speed until the mixture is crumbly and sandy in texture. This reverse creaming method is key to achieving a tender, velvety crumb. It may look unusual at first, but trust the process! Add half of the liquid mixture and combine thoroughly, then add the remaining liquid and mix just until incorporated, scraping down the bowl sides and mixing briefly for about 10 seconds. Be careful not to overmix, as this can lead to a tough cake. The batter should be smooth but not overly developed.

5-Bake the cake: Pour the batter into the prepared pan and bake for about 45 minutes or until golden brown and a toothpick inserted comes out with a few moist crumbs. Every oven is different, so start checking around the 40-minute mark. The cake is done when it’s golden on top, pulling away slightly from the edges of the pan, and a toothpick inserted in the center comes out clean or with just a few moist crumbs clinging to it.

6-Prepare for glazing: Cool the cake on a wire rack for 15 minutes, then poke holes in the cake with a skewer. These holes will allow the glaze to penetrate deep into the cake, creating those moist, flavorful pockets throughout. While the cake cools slightly, you can prepare the glaze.

7-Make the glaze: Melt the butter in a saucepan over low to medium heat once the cake is out of the oven. Turn off the heat and immediately stir in the brown sugar, vanilla extract, and buttermilk until the sugar dissolves. The mixture will bubble slightly; this is normal and helps create that delicious caramelized flavor. Add the confectioner’s sugar and stir until most of the clumps dissolve, leaving some to dissolve as the glaze sets. Let the glaze sit at room temperature until ready to pour. This resting period allows the flavors to meld and the glaze to reach the perfect consistency for pouring.

8-Final steps: Pour the warm glaze over the warm cake that has been poked with holes and allow it to soak in and set for about 30 minutes before serving. Watching the glaze seep into those little holes is almost as satisfying as eating the finished cake! The glaze quantity can be adjusted according to sweetness preference, so feel free to use less if you prefer a less sweet version.