Next: R&B Stars Reunite and It's Nothing Butta Love!

'90s R&B trio Next sat down at a table and broke bread -- or rather pizza -- to celebrate their long-anticipated reunion, and then jumped on a stage to make it official!

We got Tweet, T-Low and R.L. on their way out of Pizzeria Mozza in L.A. ... their first get-together since R.L. was tossed from the group. They started talking again after they were approached for the TV docu-series "Unsung Revisited."

Of course, they're famous for their hit, "Too Close" ... and they explained why their closeness as a group started the beef, which seems to be completely squashed now.

Wednesday night they were onstage singing another hit, "Butta Love," at the 'Unsung' screening ... partially shirtless. Some things never change.