Amy's Baking Company From 'Kitchen Nightmares' -- All the 'Unics' Should ... LEAVE US ALONE!

The owners of "Amy's Baking Company" returned to "Kitchen Nightmares" Friday to defend their volatile viral episode from last year -- and just like before, it was a total trainwreck.

Amy and Samy Bouzaglo were on the show last night and miserably attempted to tell their side of the story -- specifically regarding their vile comments on Facebook (which they claim were hacked.)

For those who missed it ... Gordon Ramsay walked off "K.N." for the first time last year -- after the baking company owners refused to accept criticism for things like pocketing waitstaff tips and picking a fight with a customer.

Although Amy and Sam insist they were hacked last year ... history repeated itself.