The Merseyside outfit kept up their chase for a Champions League spot by securing a 3-0 victory at St James' Park on Tuesday night.
"[Barkley] works so hard and he's reaping the benefits," Stones told the Liverpool Echo. "He did something similar against Arsenal. He's been brilliant, I can't praise him enough for how hard he's working for the team and that goal was a bit of success for him."
The Toffees are six points adrift of fourth-placed Arsenal in the Premier League table with a game in hand.