Chopping Block. The cooking mecca has two locations in the city, both offer hands-on and demonstration classes, but each has their own personality. The Lincoln Square location is more neighborhoody and warm. Classes here always feel intimate. The Merchandise Mart location is beautifully new and has the state of the art cooking equipment. Of course its fabulous and a bit closer to me, but I still prefer its North-side sibling.
I've made a habit now of taking a class there every few months. Demonstrations classes are $40 a person and last about 2.5 hours. You get to relax with a glass of wine and let a professional chef do all the work. You walk away with all the recipes and are encouraged to take notes during the class. The hands-on classes are $75-85 depending on the class. These are also about 2.5 hours in length but it seems longer because you're doing all the cooking. All of the ingredients are ready for you to cook with and you don't have to do any of the cleanup so the classes are always a nicer treat than cooking at home. Plus you get top of the line Viking ranges and Le Creuset baking utensils so it REALLy is better than cooking at home :)