MICHELLE Obama, like her husband, enjoys a good burger, but not as well done. The first lady brought daughters Malia and Sasha to former “Top Chef” contestant Spike Mendelsohn‘sGood Stuff Eatery in DC for cheeseburgers, onion rings, fries, and milkshakes. “They got the burgers medium,” says a spy. (President Obama was mildly ridiculed after ordering a burger medium-well in January.) “Three starving Secret Service guys were literally standing over the grill as Spike made the burgers, but didn’t eat,” our source adds. Fellow patrons had their cellphones temporarily confiscated to prevent pictures from being taken.