Preheat the oven to 350 degrees
Grease and flour two 8 inch pans ( my pans are 2 inches deep). You could also divide the batter between three 8 inch pans for slightly thinner layers which allows for an additional layer of filling.
In a medium sized bowl add the flour, baking powder, baking soda, salt and zest of 2 lemons. Whisk to blend and set aside.
In another bowl, add the milk, vegetable oil and lemon juice, and lemon extract. Whisk to blend and set aside.
In the bowl of your mixer, mix the softened butter until smooth. Gradually add the sugar and mix on medium speed 3 to 5 minutes until it is lightened in color and fluffy.
Add the eggs one at a time, mixing after each addition until the yellow of the yolk has blended in.
With the mixer on low speed, add the flour mixture and the milk mixture alternately. Begin and end with the flour (3 additions of flour and 2 of milk). Mix just until combined and smooth.
Pour the batter into the prepared pans, smoothing the tops with the back of a spoon. Bake at 350 degrees. If baking three 8 inch pans, bake at 350 for 20-25 minutes. For two 8 inch pans, bake at 350 for 30 to 35 minutes or until a toothpick inserted in the center comes out clean or with only a few crumbs attached. Let the cakes cool in the pans 10 minutes then turn out.