Weigh out your ingredients using a scale instead of using measuring cups for a more accurate recipe and bring your butter, eggs and buttermilk to room temperature. This is important, they should all be on the warm side to create a good texture. Heat oven to 350ºF and prepare a 5"x9" metal loaf pan with cake goop or another preferred pan release.
Sift together your cake flour, baking powder, baking soda, and salt.
Add the lemon extract and lemon zest to the buttermilk and set aside
Cream the butter and sugar together in the bowl of your stand mixer with the paddle attachment on medium-high speed until light, white and fluffy. 2-3 minutes.
While mixing on low, add in your room temperature eggs, one at a time, letting each mix in fully before you add in the next.
Add 1/3 of the flour mixture to the egg mixture while mixing on low, then add 1/2 of the buttermilk and mix until barely combined.
Add in 1/3 of the flour, 1/2 the buttermilk mixture, and the rest of your flour, then the rest of the buttermilk mixture and mix until just combined. Don't over-mix.
Pour your batter into a prepared 5"x9" loaf pan and bake at 350ºF for 35-45 minutes or until a toothpick inserted into the center comes out cleanly. If you use a glass pan, bake for an extra 10 minutes.
Allow the pound cake to cool in the pan until barely warm and then remove it from the pan to cool completely on a cooling rack before making the lemon glaze.