Grease and flour or line a 9 x 5 x 3 inch (approximately 23 x 13 x 8 cm) loaf pan.
Sift the flour, baking powder and baking soda into a bowl and set aside.
Cream together the softened butter and the sugar in the bowl of an electric mixer and then beat until light and fluffy. (This will take about 3 to 4 minutes once the ingredients are creamed together.)
Beat in the lemon extract and the grated lemon rind.
Add the eggs, one at a time. Add a tablespoon of the flour mixture with each egg, and beat for one minute in between adding each egg. Be sure to scrape down the bowl of the electric mixer with a spatula regularly.
Add the sour cream and the remainder of the flour mixture alternately, beating on low to medium speed after each addition until well combined.
Add the poppy seeds and the lemon juice and beat together until well combined.
Pour the batter into the prepared loaf pan.
Bake for 55 to 65 minutes, or until a skewer or toothpick inserted in the centre of the cake comes out clean.
Cool the cake in the pan for about 20 minutes before removing the cake from the pan to cool completely on a cooling rack before slicing or glazing.
Notes
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