It will be a sweet treat at Buckingham Fountain at 11 am. Wednesday as Eli’s Cheesecake serves up a 1,000-pound cheesecake celebrating both the 33rd birthday of Taste of Chicago and Eli’s being the only original vendor still participating in the Taste. The event will feature a Cirque Shanghai performance, “Happy Birthday” sung by the Australian Bee Gees troupe and celebrity cake-cutter Charlie Barnett of “Chicago Fire.” The humongous pile of ingredients for the cake includes 450 pounds of cream cheese, 70 pounds of sugar, 612 eggs and 125 pounds of buttercream icing.