Cat with resource guarding issues. Sweet otherwise. How do I stop this?

I have a male cat, he was neutered from a kitten but has always displayed some serious resource guarding issues. If he gets hold of something he shouldn't have or even just a cat toy he will sit there growling and guarding what he has. He will try his best to steal our food, he will even try to get into cupboards (which are now baby locked) to get things. If he has something he shouldn't have, he will latch on for dear life and attack us whilst we try to get it out of his grip. We have NEVER taken things that are his (toys food etc) away from him. This has been happening from a young age. Nobody has taken his toys from him or his food from him, he is always left undisturbed to eat. I've tried playing with him with cat feather toys and he will grab the end and start this behaviour. Even if you are a metre away whilst he is eating he is growling and trying to gobble it down as if we are going to pinch it.

When he isn't in this resource guarding mode he is the sweetest cat ever. Loving, confident and just an amazing cat. Can anyone help me with suggestions on how to work to stop this. Picture of my cat below. Ironically named Loki.

เว็บพนันออนไลน์