Hold your own culinary war, right at home. Here's how you do it: Sit down as a family and vote on a special ingredient. Then, everyone has to plan a dish that features that ingredient. For younger children, give them a parent or older sibling to work with, or offer ideas that don't require cooking or knives. For example, if the secret ingredient is "cheese," your child could make a cheese ball with crackers on the side, while a more mature member of the family might choose to make grilled cheese or even fondue.
For added difficulty, give each person a budget to work with and then go grocery shopping as a family. During the afternoon, everyone can take turns creating their culinary masterpiece. Enjoy the dishes together, and then fill out "secret ballots" on which dish was the most successful. Reward the winner with a fun apron or chef hat.