Impossible Leavening

In comedy shows, yeast tends to be treated as far more volatile and powerful than it actually is. A less than stellar baker will add more yeast to a recipe than it needs, often many times more, and the dough reacts explosively. If you're lucky, all that you get is a mess in the kitchen, or a pizza that nearly fills the oven as it bakes. However, it's just as common to see the dough explode all over the kitchen or, in extreme cases, come to life. Occasionally, baking powder and baking soda, also known for their leavening properties, can cause much the same problems.

Compare Oven Logic, for when the disaster is the result of temperature instead of yeast. If the aspiring chef combines the two, you might as well just start saving for a new kitchen altogether.

Examples of Impossible Leavening include:

Comic Books

• There's a Goof Troop story with this happening in Pete's kitchen, then whole house: When instructed to add 3 drops of ultra-concentrated yeast five minutes before the cake is done, Pete just poured the whole bottle in at the start and went for the TV.

Western Animation

• In an episode of Ed, Edd 'n' Eddy, the trio make pizza. Eddy, ignoring Edd's instructions for the proper amount, dumps in the whole container of yeast for the dough. The dough rises so much that Eddy's fist gets stuck in the dough when he tries to punch it down, and Ed has to bellyflop on it to do the job.
• In Hey Arnold!, the kids of the city work on the world's biggest pizza puff in a bid to break a world record. All seems well, until Sid reveals that he misunderstood "tsp" in the recipe. Instead of "teaspoons", he read it as "ten square pounds"! The resulting explosion of dough takes a good deal of the next day to wash off of the streets.
• Weaponized by The Breadmaster, a villain on The Tick (animation).
• Taken to its logical extreme in one episode of Muppet Babies, where an Imagine Spot has the fifty-foot Piggy Dough-Girl rampaging through the city: Bunsen tells Beaker to use the "Beast Blaster" to destroy it, but he ends up firing a "Yeast Blaster" at it instead, causing it to grow into a full-fledged Planet Eater.

Live Action TV

• I Love Lucy. In "Pioneer Women", when the oven containing the result of this trope was opened, the bread came out in a huge oven-shaped loaf, far longer than the oven was deep, stretching all the way across the kitchen and pinning Lucy to the opposite wall.
• The Three Stooges did this, but not with bread - with beer! In "Beer Barrel Polecats", the trio were trying to make their own beer. The directions said to use three cakes of yeast, and each stooge, not knowing the others had already done so, put in three cakes. It ends up spilling out of the large crock they're using to brew it in and they eventually fill a bathtub full.
• On Fraggle Rock, Ma Gorg puts too much yeast and other ingredients in her souffle. She ends up fighting it until it explodes and leaves a huge mess.

Real Life

• Averted because the gluten structures will collapse long before the gases reach critical density to cause an explosion. Without the gluten structures to hold the gases in, the gases will simply poof out of the bread. This will result in a product that kinda looks like Swiss cheese. Also, too much yeast growth will end up eating up the dough, which will result in weakening of the gluten structures rather than extreme expansion.