In a perfect world, we’d all do a stodge in a restaurant kitchen and learn how to cook a piece of meat the right way every time, without pressing the skin between thumb and forefinger. The truth is that no cookbook — not even one by that old goat Escoffier — can teach you what experience will impart. A cooking tour is a happy medium: learn by doing without anyone yelling at you for forgetting to fire the souffles. Choose the tours that are less about sightseeing and more about technique, like hand-making pasta and bread, or sausages and charcuterie. Also, go somewhere that has relatively similar ingredients to your home state so the skills translate when you get back.
Go here: Tuscany and Emilia Romagna, Italy; Provence, France; Catalonia, Spain; Oaxaca and Veracruz, Mexico.