Preheat your oven to 350°F (175°C) and grease a standard loaf pan.

In a mixing bowl, combine the flour, baking powder, baking soda, and salt.

In a separate bowl, cream together the softened butter and sugar until light and fluffy, about 3-4 minutes.

Add the eggs, vanilla extract, lemon zest, and lemon juice to the creamed mixture and mix until well combined.

Gradually incorporate the flour mixture and buttermilk, alternating between them until just mixed. Avoid overmixing.

Pour the batter into the prepared loaf pan and smooth the top.

Bake for 50-60 minutes, or until a toothpick inserted in the center comes out clean.

Let the loaf cool in the pan for about 10 minutes before transferring to a wire rack to cool completely.