Coat a ten-inch tube pan or bundt pan with solid vegetable shortening then either flour or sugar. I use granulated sugar because it doesn't leave white areas on the cake. Alternately, you can use Wilton Cake Release.
Preheat oven to 350 degrees F.
Sift the flour then measure it using the scoop and level method for measuring flour. Next, sift the salt and baking powder together and add it to the flour mixture.
In the bowl of your electric mixer, mix the butter, shortening, and sugar until light and fluffy. Stop the mixer and scrape down the sides.
Add eggs, one at a time, beating until the yellow disappears after each addition.
Mix in Amaretto. Stop the mixer and scrape down the sides with a spatula.
Add the milk and flour mixture alternately, beginning and ending with the flour mixture. Stop the mixture and scrape the sides. Give the mixer another whirl to combine everything.
Pour batter into prepared tube pan, leveling the top with a spatula.
Bake for 1 hour 20 minutes. (Start checking at 1 hour 15 minutes; your oven may be hotter than mine.) If your cake pan is dark, it may take less time, and if it is light, it may take more time. You'll need to watch it closely and test it.
Cool the cake in the pan on a wire rack for 30 minutes before inverting it on a platter. (Instructions for adding the glaze are below.)
Optional glaze
Add the sugar, butter, and water to a small saucepan. Whisk it and bring it to a low boil and boil for 2 minutes or until the sugar is dissolved. Remove the mixture from the heat and add the amaretto. Whisk to combine. Slow pour over cake.