What cooking or baking mistakes have you made?

[wnylib]

My most embarrassing mistake was when I was 11 years old.

My father's family was going to my widower grandfather's house to celebrate his birthday. Everybody was bringing a dish to pass. While my parents were out shopping, I baked a cake (box mix). But then I discovered that we were out of powdered sugar for the frosting. I had never made any kind of frosting without it, so I found a recipe in my mother's cook book for boiled frosting, using granulated sugar.
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I decided to take a shortcut. I boiled the water and stirred it into the granulated sugar, which dissolved. So I figured that's all I needed to do. Grandpa liked peanut butter frosting, so I added some to the sugar and water mix. It looked ok when I spread it onto the cake. Covered it with foil.

When we got there I proudly announced that I had made a cake and uncovered it in front of aunts, uncles, and cousins. The sugar had crystallized again because it had not been boiled. The cake was covered with granulated sugar and peanut butter. I was horrified.

My grandfather thanked me and said not to worry. We could still eat it the cake after scraping off the top.