Exactly this happened to my mum when she tried making homemade frozen pizza without prebaking it. Either this is a store bought frozen pizza that thawed in a serious manner or something similar happened.
Source: I sustain myself on a healthy 33% Pizza diet.
I d rather have 2 to 3 (for critical, mid, and test systems) ssh keys that are regularly rotated than 1 key per machine. I m not gonna balance 50 ssh keys; neither enter my password every time i jump hosts.