Preheat your oven to 350°F (175°C). Grease and flour a 9×5-inch loaf pan, or line it with parchment paper for easy removal.
In a medium bowl, whisk together the flour, baking powder, baking soda, and salt. Set it aside.
In a large bowl, whisk the eggs, sugar, sour cream (or Greek yogurt), and oil until smooth.
Stir in the lemon zest, lemon juice, vanilla extract, and lemon extract if you’re using it.
Gradually add the dry ingredients to the wet ingredients. Stir until just combined. Be careful not to overmix!
Pour the batter into your prepared loaf pan and smooth the top.
Bake for 50–55 minutes, or until a toothpick inserted in the center comes out clean.
Let the loaf cool in the pan for 10 minutes. Then, transfer it to a wire rack to cool completely.
For the glaze, whisk together the powdered sugar, lemon juice, and zest until smooth and pourable. Once the loaf is cool, drizzle the glaze over the top and let it set before slicing.