In a large bowl, using a mixer, combine the butter and sugar until creamy. Add the eggs, 1 at a time, beating well after each addition. Add the flour and milk alternately, beginning and ending with the flour. Stir in the lemon extract. Spoon the batter into the prepared pan.
Place the pan in a cold oven and set the oven temperature to 325 degrees F. Bake cake for 1 hour. Increase the temperature to 350 degrees F and bake for 30 minutes more.
Cool the cake in the pan for 10 minutes, and then turn out onto a wire rack to cool.