To the bowl of a stand-up mixer, with the hook attachment, add the yeast/milk mixture, melted butter, eggs, salt and flour. Turn the mixer on medium speed and knead for 5 to 8 minutes, until the dough has formed a smooth ball. Rub the inside of a clean bowl with olive oil or coat with cooking spray and transfer the dough to the bowl. Grease the top of the ball of dough and cover with a clean kitchen towel. Allow the dough to rise in a warm place for about an hour or until doubled in size.