Roast or Toast?
This is not about meat and two veg done in the oven v. a slice of bread under the rack it is, instead, a humorous variation on introducing a speaker.
There is an art and a time restraint on any Roasting activity. Like any short speech you need to prepare. Make a list of the most intriguing and unique accomplishments or characteristics of the speaker you are to introduce. Prepare an introduction that flows from one thought to another, including the tall story or exaggerating idiosyncrasies with a semi-serious demeanour.
Whatever you do say, make sure you include a pause to affect the audience’s digestion of your jovial intent.
Top tip – have fun whilst you are Roasting, but not at the speakers expense. They will always get you back! Remember that; they are speaking next!