Preheat the oven at 325°F (165°C) and grease and flour generously a 12-cup Bundt pan. This helps the cake slide out easily once it’s baked.
In a medium bowl, whisk together the all-purpose flour, baking soda, salt, and lemon zest until well combined. Set it aside.
Using an electric mixer in a large mixing bowl, beat the soft unsalted butter with granulated sugar at a medium speed for 1-2 minutes or until the mixture lightens in color and becomes fluffy.
Add the eggs one by one, mixing well after each. This ensures that the eggs are evenly incorporated.
Gradually add half of the flour mixture, followed by half of the sour cream and half of the lemon juice. Mix on low speed. Add the remaining flour mixture and sour cream. Mix gently until the batter is thick and well combined.
Add the lemon extract (if using) and give it a final mix to ensure it’s evenly distributed throughout the batter.
Pour the batter into the prepared bundt pan and smooth the top with a spatula. Tap the pan lightly on the counter to release any air bubbles.
Place the pan in the oven and bake for approximately 50-60 minutes, or until a skewer inserted into the center comes out clean. Check it after 60 minutes since oven temperatures may vary.
Allow the cake to cool in the pan for about 10 minutes. Then, transfer it to a wire rack to cool completely. Don’t skip this cooling step to avoid the cake sticking to the pan!