Toni suffered an injury during the Bavarian side's weekend encounter against Karlsruher and might therefore miss the Champions League game against his former side.
Prandelli, despite looking forward to seeing Toni again, would prefer if the Italian striker would miss this clash.
"It's always better if Luca (Toni) is not there because we know him well," joked the former Parma coach.
"But kidding aside, it will be a pleasure to see him on the pitch after the two extraordinary years he spent with us.
"Obviously, though, it would be nice to make him eat his heart out."
Prandelli then moved to his serious mode to comment on the clash against the German champions.
"It's the most important game of my career as a coach, against a team full of huge players," he continued.
"Bayern is a prestigious club which plays in the most beautiful stadium in the world."