Beware of the Purple Peanut Butter

The book begins with your character geting dropped off at your cousin's house over summer break. You and your cousins are bored, so you play "hide and go seek". Your hiding place leads you to the basement that your uncle strangely told you to stay out of. In the basement, you discover a fridge that contains a purple, slimy goop in a container that smells tasty and an old, chocolate slice of a cake that has no smell at all. If you eat the goop you'll begin shrinking which it will lead you to fighting a mouse, finding a doctor, or finding the fridge at the dump after you discover your shrinking. If you eat the slice of cake, you'll begin to grow taller and taller which will lead you to running from the police/army because they think your an alien, joining a circus, or finding the baker's shop who made the cake.