Not 100% sure why the server is crashing, I’ve had a couple of looks though but cant see anything obvious unless I’ve missed it. Would be nice if someone more experienced could take a look at whats going wrong.
Link to crash report Crash Report - Pastebin.com
It looks like the Recipes+ mod is the cause of the problem.
Could you post the crash report text file as located in your server folder under \crash-reports\crash-2019-01-31_01.33.04-server.txt?
So I can’t be one hundred percent certain, without taking a closer look at the log.
It looks like you might be running out of memory while trying to load the game, hence the Minecraft class being unavailable.
If you are able to, please try allowing 2GB (or more) of ram, and seeing if that makes a difference. If it does…we know the culprit, if it doesn’t then 
yeah i fixed it. It was the recipes mod that broke it.
Thanks for the help everyone.