Hundley (18-of-21, 261 yards, one interception) hooked up with Johnathan Franklin, Joseph Fauria and Devin Fuller on scoring strikes during the big frame for the Bruins (8-2, 5-2 Pac-12).
Franklin compiled 66 rushing yards on 19 carries as UCLA retained the lead of the Pac-12's South Division ahead of next week's showdown with second-place and 22nd-ranked Southern California.
The Cougars (2-7, 0-6), meanwhile, remained winless in the conference while playing their first game without star receiver Marquess Wilson, who was suspended and then left the team this week.
Connor Halliday amassed 330 yards on 26-of-43 passing efficiency for Washington State.
Video of Victoria’s Secret models trying to 'twerk' hits Instagram
Britney Spears debuts 'Perfume' video