No answer here, but to clear up for some people who have already answered: I think OP is referring to making a toast, like at a wedding. Not toasted bread. Though I could be mistaken.

In a similar vein, how did the word toast come about to have two totally different meanings? (One being, sliced and browned bread. The other a raising of glasses in honor of things.)

This thread here has a good comment from /u/agentdcf that gives a brief rundown of the origins of toasted bread, which appears to be in the Victorian era.