Chris Willman Senior Music Writer and Chief Music Critic In “Into the Woods,” the audience laughs at the gluttony of the Little Red Ridinghood character, especially in the earliest, most deliberately cartoony parts of the production. But in a sense, the crowd is getting off on gorging, as well, since this is the ultimate having-your-cake-and-eating-it-too show. Stephen Sondheim and James Lapine weren’t too proud to cook up their 1987 classic with copious amounts of Mad magazine-style spoofery — or Looney Tunes-level laughs, even — and yet you can feel like those seemingly empty calories are justified, knowing you’ll be gulping back salty tears by the end. “Into the Woods” is as overstuffed with characters and ideas as any musical ever has been, but if everyone does their job right, you leave feeling like you’ve just been fed a perfectly balanced meal, and not a morsel more.