When I was in high school, I had a friend who I had many "adventures" with. One day we were at her house and we decided to make some cookies. I was on board with this, because I was really interested in her brother, and what teenage boy doesn't love cookies? (I met him at school and was starting to be 'friends' with him when I met her. I didn't know they were related for about a month and a half)
So, back to these cookies. We were using her mom's go-to chocolate chip cookie recipe, guaranteed to be delicious. I was reading the ingredient list, and Friend was grabbing everything and putting it on the counter. It's important to note that Friend was child #5 of 6 in her family, so her mom bought almost everything in bulk. Things like flour/sugar/rice were in smaller, plastic bins.
We got to work, mixed up our dough, but we could only find one cookie sheet, so we resigned ourselves to baking several batches. But the first batch turned out really weird. Picture a fried egg. The center mass of each cookie (where the chocolate chips and nuts were) was bigger, but where the cookies had spread, was almost paper thin. Friend called her mom, described the problem we were having, and Mom said it sounded like we needed more flour. So, we added more flour. And more flour. And More flour. It was still not working. If anything our cookies looked worse.

So we decided it didn't matter how the cookies looked, we would eat the misshapen monstrosities anyway. I mentioned that I liked her brother, right? Around the time we decided to just eat them, he came home. Before tasting them myself, I offered him a cookie. He took one bite, then ran to the sink and not only spat it out, but he kind of retched a bit as well. I was almost in tears, until I absently nibbled on a cookie, and ran to the garbage can. As it turns out, our cookies were indeed lacking flour. Friend had mistakenly grabbed powdered sugar instead. We made cookie dough with no flour at all, and about 8 cups of powdered sugar. They were terrible. I was embarrassed that I had offered one to the Love of My Life.
I don't think I'll ever live that one down. You see, Friend is now my SIL; I married her brother, and my MIL knows far too many embarrassing Teen Twiggy stories since SIL and I got into a great many interesting situations together.
*Edited to remove huge emoticons