The pair - who played A.C. Slater and Kelly Kapowski in the US teen comedy - met up after Tiffani invited Mario to appear on her new show Dinner at Tiffani's.
Tiffani is a dab-hand at cooking up a storm and is joined by celebrity guests in the kitchen to talk all things food and entertainment. So who better to ask on than her old pal Mario?!
While the cameras weren't rolling, Mario and Tiffani posed for a selfie together. Sharing it on Twitter, Mario told fans: "Loved catching up with my girl @TAThiessen ! Had a fun time on her show 'Dinner At Tiffani's'."
The picture definitely sent SBTB fans into a spin, and many were quick to comment.
One posted: "@MarioLopezExtra @TAThiessen Saved By The Bell Reunion!!!!" Another, meanwhile, added: "Wait...do Zack & Jessie know about this?"
Aww, it's great to see A.C. and Kelly reunited!
Since finding fame on SBTB, both Mario and Tiffani have gone on to have successful TV careers. While Tiffani has starred in shows such as 90210 and more recently White Collar, Mario presents his own programme Extra.
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