If my recent lunch at Edge had concluded with the bread and butter, I would have been happy. Of course, it didn’t—several fabulous courses followed—but it was the house-made pain au levain and cultured butter I couldn’t get out of my head. I knew I couldn’t reproduce this Sonoma restaurant’s bread, which John McReynolds, Edge’s culinary director, spent many months perfecting, but I figured the butter might be within my skill set. What gave it such incredible flavor? In a word: cheese.