INGREDIENTS - CAKE
3 cups unbleached all-purpose flour
1 teaspoon salt
1 teaspoon baking powder
1/2 teaspoon baking soda
3/4 cup buttermilk, room temperature
1 tablespoon vanilla extract
3 tablespoons fresh lemon juice
3 tablespoons fresh grated lemon zest
2 1/4 sticks unsalted butter, cut into chunks and softened
2 cups sugar
3 large eggs, room temperature
1 large egg yolk, room temperature
INGREDIENTS - GLAZE
1 3/4 cups confectioners' sugar
1/4 cup fresh lemon juice
1 teaspoon fresh grated lemon zest
1. Adjust an oven rack to the lower middle position and heat the oven to 350 degrees F. Grease and flour a 12-cup Bundt pan.
2. Whisk flour, salt, baking powder, and baking soda together in a medium bowl. In a small bowl, whisk the buttermilk, vanilla, lemon juice, and lemon zest together.
3. In a large bowl, beat the butter and sugar together with an electric mixer on medium speed until light and fluffy, 3 to 6 minutes. Beat in the eggs and egg yolk, one at a time, until combined, about 1 minute.
4. Reduce mixer speed to low and beat in one-third of the flour mixture followed by half of the buttermilk mixture. Repeat with half of the remaining flour mixture and the remaining buttermilk mixture. Beat in the remaining flour just until incorporated.
5. Scrapte the batter into the prepared pan and smooth the top. Gently tap the pan on the counter to settle the batter. Bake the cake until a toothpick inserted in the center comes out with a few moist crumbs attached, about 50-60 minutes, rotating the pan halfway through baking.
6. Let the cake cool in the pan for 10 minutes, then flip it out onto a wire rack to cool completely, about 2 hours, before serving.
7. While cake cools, whisk together all glaze ingredients in a small bowl until smooth. Let sit until thickened, about 25 minutes. Pour glaze over the top of the cake after it has cooled completely, letting the glaze drip down the sides. Let glaze set before serving, about 25 minutes.