Quote Originally Posted by Hanna View Post
But I think that toast as in "toasted bread" is not usually put into plural...
I think it is normally uncountable in the UK, where people speak of slices or pieces of toast, but in the US, it can be countable. E.g. the very first definition in the Merriam-Webster's Unabridged Dictionary says:
1 a : a slice or piece of toasted bread
used in the phrase as warm as a toast
Notice that "a" before "toast".

Longman, on the other hand, contains a definition for the phrase "warm as _toast" (no article).