Before you can say “Sleighride,” the Musical Theater Project is back with their annual holiday treat! The show isn’t complete until everyone joins in on “White Christmas”—but that’s just one of several dozen songs that appeal to every generation. The hits range from “Winter Wonderland,” “Let it Snow” and “Have Yourself a Merry Little Christmas,” to Irving Berlin’s 101-year-old salute to Santa Claus and the inevitable tributes to Rudolph, Frosty and that mean one, Mr. Grinch. “A Christmas Cabaret” will feature TMTP artistic director Bill Rudman, music director Nancy Maier, Joe Monaghan, and Sandra Simon.