I have a couple. Once I decided I could cut corners and make egg fried rice better and quicker than the recipe stated, which ended up terribly burnt and the smell stuck for days, even when I threw away the pan! Another was a pasta bake, when I failed to misread how much water to add (if I added any). Awful! Burnt, crisp pasta, totally inedible, but my guests were nice about it, they just explained that they weren't as hungry because they work night shifts!
I've had many more kitchen disaters, but have come a long long way with my cooking skills. I panic less now, as we have a chip shop next door, so if I bugger it up, it's a few doors down I go