If it’s the garbage disposal side, have you tried septic tank enzymes? I would do that before vinegar, before any other chemical.
Here's a helpful video: https://www.youtube.com/watch?v=r25zMpTPotA
Hi Pat, here is a cheap and easy way to try to clear that clog
Quite often a plumber's snake is needed.
Here's a post I wrote that might help you - https://chascrazycreations.com/unclog-drains-toilets-with-out-plunging/
Try using Sink and Plughole unblocker. If it could be caused by Fat build up - maybe use strong Dish liquid and hot water left overnight and topped up in the morning. If still blocked you may need to remove the drain cover and investigate.
Hi there, when it's really bad - for clogs that won't dissolve with vinegar and hot water - we've used this tool and it works like a charm. https://www.hometalk.com/2251857/how-to-unclog-a-sink-like-a-pro