The Scottish international made just 13 starts for the Toffees last season under David Moyes, but he has turned his fortunes around and scored nine goals so far this campaign.
The 27-year-old has been an integral part of Everton's UEFA Champions League pursuit, something which has delighted his manager.
"I do believe that Steven Naismith has been the find of the season in terms of the level of performance he has brought to the side in that central position," the Spaniard told the Liverpool Echo.
"We've seen the player that we all saw at Kilmarnock, emerging as an incredibly bright young footballer.
"He then went to Rangers and became a match-winner.
"He is enjoying his football and works extremely hard and he is one of the brightest footballing brains I have ever worked with.
"He is someone that can take information and execute it down to perfection and he has been a real strong character in the dressing room, bringing those strong attributes to the group."