nostr:npub175l80yqmw7jrh79385lpcdaqdgwvxm25leflgqqedmjpkalphvnqyv55we Good question! The OED has an older meaning for the verb "roast" as burning someone alive, so I would guess that roasting someone as a very mild form of torment comes from that, but I can see how it would also benefit from the resonance with "toast."