Cookies might seem like a warm and cozy business to be in but—just to borrow from an old saying—it can get awfully hot in the kitchen. Packaged cookies are actually an $8.2 billion segment, according to the latest data from Chicago-based research firm IRI, and competition is fierce. Household names like Keebler, Pepperidge Farm and Little Debbie dominate the store shelves. The mighty Mondelez alone—which makes Chips Ahoy and Oreo—controls nearly 40 percent of the segment. Even the humble Girl Scouts who come to your door in green uniforms and pigtails ship some $700 million worth of cookies a year.