In Bologna, food rules. So it came as no surprise that the pastry shops there would be remarkable. And none more so that this one, Atti. Even they call their sugar-dusted ciambella “a marvel.” Blackberry tarts. Old-fashioned individual custards. Almond-covered mountains of sweets. And the fabled Torta Bolognese, a rich, almond-flavored cake that incorporates layers of sweetened pasta (tagliatelle) among its ingredients. The recipes for many of these (and more) made their way into my friend Nick’s Great Italian Desserts, the research for which prompted this visit to Bologna. Sweet research, indeed.