America’s amateur cooking competitions can make ”Iron Chef” look like a kindergarten class. Sutherland spent a year following a few culinary dreamers and schemers through the cream of the more than 1,300 contests held annually. She captures the tension of the $50,000 National Beef Cook-Off and the big doughboy of them all, the million-dollar Pillsbury Bake-Off, where an ill-conceived garnish can spell disaster. But those moments are too few, and Sutherland’s writing can get corny (”Yum!” and ”fancy-schmancy” make regular appearances). Still, the overall effect is like a warm Tunnel of Fudge cake.