On Fat Tuesday, starting early, lines thread around the mom-and-pop bakeries of greater Philadelphia. Drive out to Bucks County, parts of Jersey, or Pennsylvania Dutch Country and you’ll see the same. Doors swing in and out. The occasional snowflake drifts in, drawn like I am to the scent of sugar and sizzling fat. It’s Doughnut Day, and bakers have been working ‘round the clock to feed demand.