Oh dear.
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When I was a kid, I was at my grandparent's house, and thought I'd make lemon bars for dessert that night. I'd made them several times before. But that time, when I added what I thought was the baking powder, everything in the bowl fizzed up. Which had never happened before. I went on cooking and didn't think much of it.
The look on my grandpa's face when he tried the first one was priceless! He obviously didn't want to hurt my feelings, but they were just awful!
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We ended up having a good laugh about it, and feeding them to the dog.
Well...trying to. The dog wouldn't eat them either. :p