Ingredients
2½cupcake flour
1tspbaking powder
1tspbaking soda
½tspsalt
¾cupbuttermilk,room temperature
3tbspzest,grated
¼cuplemon juice,(3 lemons)
1tspvanilla
1¾cupsugar
1½butter sticks,softened
3large eggs
1egg yolk,room temperature
3cupspowdered sugar
3tbsplemon juice
2tbspmilk
Preparation
In a medium bowl, combine flour, baking powder, baking soda and salt, set aside.
In a liquid measuring cup, combine buttermilk, lemon juice and vanilla, set aside.
With a stand mixer, beat sugar and lemon zest until smooth. Transfer ¼ cup sugar mixture to small bowl, cover and set aside.
Add butter to remaining sugar in mixer and beat until light and fluffy. Beat in eggs and egg yolk one at a time. On low speed, add flour mixture in 3 additions, alternating with 2 additions of the buttermilk mixture. Beat until smooth.
Pour batter into a greased and floured 10×15-inch pan and smooth the top with a spatula. Bake at 325 degrees F, for 25-35 minutes, or until golden brown. Transfer to wire rack and let cool 10 minutes.
For the glaze, whisk powdered sugar, lemon juice and milk until smooth. Gently spread over warm cake and sprinkle reserved sugar mixture evenly over the top. Serve warm or cool for at least 2 hours.
