The Perfect Hamburger and Other Delicious Stories by Alexander McCall Smith

The Appetizer: The Perfect Hamburger
When a snazzy fast-food chain moves into town, business at Joe's favorite hamburger restaurant begins to suffer. He gets an idea that's sure to bring back the diners, but there's jsut one problem: the secret recipe for the burgers is missing! Can Joe figure out the ingredients to recreate the perfect hamburger before it is too late.

The Entree: The Spaghetti Tangle John and Nicky, forced to live with their vegetable-loving Aunt Rebecca, dream of eating spaghetti for every meal. So when they enter a recipe contest and win a trip to Mr. Pipelli's spaghetti factory, they couldn't be happier! But are they prepared for an encounter with the spaghetti spinner?

The Dessert: The Doughnut Ring Jim thinks a doughnut sale is the perfect fund-raiser to help his friend, Mr. Pride. And it is- at first. But when an email chain asking for donations gets out of control, Jim finds himself up to his ears in doughnuts! Will he ever be able to see all the stock and stop the doughnut ring for good?