AMERICANS MAKE SUCH bad cappuccinos, most of us don’t even know from a good one. We foam the milk till it’s hellishly frothy. We shower the cup with cinnamon. Nicolas O’Connell and his bosses at Philadelphia’s La Colombe Torrefaction want to right our wrongs. When they are not running their coffee shop, they visit the country’s best restaurants, schooling the staffs in how to properly handle an espresso machine. When you oversteam the milk, explains O’Connell, you get big “shampoo-like bubbles.” When you overheat the milk, you get a smell like “aged goat cheese.” You do not want shampoo or goat cheese in your cappuccino.