For the Cake:

• Preheat oven to 300°. Cover inside of 10 inch tube pan with non-stick spray. Set aside.
• To make the butter-egg mixture: Using a stand mixer or electric hand-held, beat the butter well until light in color and fluffy. Add the sugar and again beat well until the graininess of the sugar is gone. With a stand mixer it will take 10-15 minutes. One at a time add the eggs and beat only until the yellow disappears.
• Juice mixture: Stir Key lime juice, milk, zest and vanilla together.
  
• To make the batter: Mixing by hand, gradually add the 4 cups of flour to the butter-egg mixture alternating with the key lime juice, vanilla and milk mixture. Begin and end with flour. Mix well but just enough to incorporate all ingredients. You don’t want a tough pound cake!
• Pour evenly into the tube pan and tap pan on the counter to loosen any air bubbles.
  
• Bake for 1 hour and 45 minutes at 300° F or until cake tester comes out clean.
• Cool on a cooling rack for 20-25 minutes in the pan then transfer from pan to cooling rack and allow to cool another hour or until completely cool.
• The cake is far better the following day or 2 days later.
• For the Icing:
• Using a hand mixer beat cream cheese and butter in a large bowl until well mixed.
  
• Add confectioner’s sugar and beat well until completely smooth and fluffy.
• Add key lime juice, zest and vanilla and mix until all ingredients are incorporated.
• Ice the cake with a relatively thin layer of icing.
• This recipe makes quite a bit of icing. After icing the entire pound cake I fill the middle hole with the excess icing. When the cake is served icing can be taken from the middle and dolloped along the side the slice of cake.