Preheat the oven to 350°F.

Spray a 9x5-inch loaf pan liberally with nonstick cooking spray. Set aside.

Place the butter, sugar, lemon zest and vanilla extract in a large mixing bowl. Using a hand mixer or stand mixer fitted with a paddle attachment, cream the ingredients together on medium speed until pale and fluffy, 3-4 minutes. Add two of the eggs, beat for 20-30 seconds until mostly combined, then add the remaining egg and the sour cream, continuing to beat until the mixture is smooth.

Sift the flour, baking powder, and salt into the bowl. Beat the mixture on low until it becomes a smooth, thick batter.

Transfer the batter to the prepared loaf pan.

Bake the cake on middle rack of oven until a toothpick inserted in the center comes out clean, 60-75 minutes.

Check to see that cake is done. Remove from oven or add time as needed.

Allow the cake to cool in the pan for 15-20 minutes. To release the cake, run a butter knife between the edge of the cake and the pan. Turn onto a large plate.

Allow the cake to cool for 1-2 hours before slicing and serving.