The rumor mill never sleeps: Before another decade has turned, we hear, the Twin Cities will be home to both an Ikea and a Krispy Kreme outlet. Now, for all of us who have packed into a minivan and driven to suburban Chicago to check out a 40-million-square-foot warehouse of modular Scandinavian design, it would be impossible to overstate the value of an Ikea--though their flimsy furniture has a demonstrated half-life of six months. But as for Krispy Kreme: Let us be the first to declare that its virtues have been exaggerated. Who needs Krispy Kreme's heavily processed toppings and white-bread texture when a perfectly wonderful bakery like Blackey's is open seven days a week right around the corner? Granted, you can't buy coffee at this Northeast redoubt, and there's often no one standing behind the counter when you arrive. Blackey's does much of their business selling breads and rolls to restaurants, so although they value the walk-in customer, you're not paying 65 cents for atmosphere. What you can buy for that amount are some serious doughnuts. These are not airy confections like you get at the double K. No, Blackey's bakes 'em heavy and cakelike. There's nothing wrong with their powdered jelly doughnut--or any of the Danish and Polish specialties they bake up. But their ordinary glazed donut is a classic, showcasing a dense spongelike mouthfeel, and, when examined in cross section, a handsome, natural-looking yellow interior. In every sense, these are doughnuts with gravity.