The new Pilgrim's Bounty holiday has made levelling cooking an absolute breeze (in case you had not already figured that out).
The screen shot shows my level 7 priest with 315/375 cooking skill, all levelled using just the 5 holiday foods (+the spice bread).
As you can see, Slow Roast Turkey is still orange at 315, so I'm not sure how much further you can level up, but I'll see when I catch some more turkeys.