1. Prepare the Crust:

1. Preheat the oven to 350°F (175°C). Grease and flour a 9×13 inch baking pan.
2. In a large bowl, cream the softened butter and sugar together until light and fluffy. Add eggs one at a time, beating well after each addition. Stir in the lemon zest and lemon juice.
3. In another bowl, sift together the flour, baking powder, baking soda, and salt. Add this mixture to the creamed ingredients alternately with the milk, beginning and ending with the flour mixture. Mix until just combined.
4. Pour the batter into the prepared pan and spread evenly. Bake in the preheated oven for 25-30 minutes, or until a toothpick inserted into the center comes out clean.
5. Allow the cake to cool in the pan for 10 minutes, then turn out onto a wire rack to cool completely. Serve plain or with a dusting of powdered sugar.