Preheat oven to 325 degrees F.
Grease and flour an 8x4 inch loaf pan. I like to lay a strip of parchment down the center for easy lifting.
In the bowl of a stand mixer with the paddle attached, beat the butter until creamy and smooth.
Add the confectioners' sugar and beat until creamy, scraping sides of bowl often. Add the vanilla and beat until well blended.
Add one of the eggs and beat on low until incorporated, then increase speed and beat on medium for 30 seconds or until smooth. Repeat, adding second and third eggs one at a time and beating until smooth (about 30 to 40 seconds after each egg is mixed).
Remove the bowl from the mixer stand and sift in the flour. Stir with a heavy duty scraper until flour is incorporated into the batter, then put the bowl back on the mixer stand and beat with the paddle for about 10 to 20 seconds to ensure the flour is completely blended.
The batter should be fairly thick. Spread it evenly in the pan.
Bake in lower third of oven for 60 to 70 minutes (check at 60) or until cake is brown and crusty and a skewer inserted in the center comes out with moist crumbs.
Let the cake cool for about 10 minutes, then loosen the sides gently without removing from the pan. Let it cool in the pan for another half hour or so, then remove from the pan and let cool for several hours. For a more Sara Lee like texture, wrap the completely cooled pound cake in plastic and freeze overnight. Let thaw, then slice.