What mistake do you make in the kitchen most often?  Omitting ingredients, forgetting to preheat the oven, or maybe not setting the timer?  I’ve made all of these more than once, but I find the thing I do more than these is trying to cut a recipe in half, and forgetting by the end of the ingredient list that I’m halving the recipe and adding the whole amount of the last two or three things.  Sometimes it ends in disaster.  Sometimes not.