Well, how is the obedient disobedience tactic working for you?

If it's going well, then great. If it is not, then try this. Give him a boundary near the kitchen where he can see you but not enter the kitchen at all. Put him in a down stay, and keep him there. Return him to the spot where you have chosen the boundary to be, if he breaks and enters the kitchen.

I don't allow animals in the kitchen especially when I am cooking, my cat even has been trained to not enter the kitchen unless she is called. When I was young girl, the family had a cocker spaniel, and my mother burned her with boiling water. The dog use to follow her everywhere and she tripped my mother going to the sink.

I would also keep the counters clean also, so if you aren't home there is nothing he can get into.