Grease and flour a 10-inch tube pan. Sprinkle sliced almonds over the bottom.
In the bowl of a stand mixer, cream the softened butter, margarine and sugar for about 5 minutes.
Crack the eggs into a separate bowl and whisk them together. With the mixer on medium speed, gradually drizzle the eggs into the bowl. Beat in the extract.
With the mixer on lowest speed, add the flour and the milk alternately, stopping every so often to scrape the sides of the bowl.
Scrape the batter into the prepared pan pan.
Put the pan in the cold oven, close door, set timer for 350 degrees F.
Bake for about 90 minutes. Be sure to check after about 70 minutes in case your oven runs hotter than mine, but mine did take 90 minutes.
It should be pretty easy to tell when this is done. The outside will be brown and crusty and the cake will be fragrant. If you want to be extra sure, stick a meat thermometer in and make sure the crumb is over 205 degrees F.
Loosen the hot cake by sliding a knife between the cake and the sides of the pan. Let the cake cool in the tube pan for about 10 minutes, then carefully invert so that the almonds are on the top.