The "Jersey Shore" mainstay shared the clip via social media on Saturday ... documenting a nice family dinner Thursday night that quickly evolved into a nightmare scenario.

A family meal starts out innocently enough ... with Mike sitting at the table and his 2-year-old son Romeo sitting in the chair beside him. The little guy puts a bit of pasta pesto gnocchi in his mouth -- and that's when things take a turn.

Romeo's almost immediately in distress ... coughing and starting to cry -- and Papa Mike's on his feet within seconds, checking in on his eldest child before Romeo collapses into a hunched-over position.

One of the two adults Sorrentino is with can be heard clearly saying "He's choking, he's choking" with a woman who appears to be Mike's wife Lauren heading to the kitchen for some water.

MS smacks his son on the back repeatedly, trying to dislodge the food from his windpipe which seems to work eventually ... with Romeo letting out a loud cry as his mother seems to use some kind of tool to get the food out and pulls him into a tight embrace.

The father-of-three posted a couple pics of his kids after the vid ... and gave more details on the ordeal -- basically saying Romeo got the pasta stuck in his throat while applauding himself and his wife for staying calm despite the horror of the moment.