A pizza, specially made by Mike Demore of Demore's Pizza in Millvale, PA, that has 4 layers of extra cheese. If a "DoubleDouble" is called in for an order, a siren sounds, chaos insues, and Mike will make the pizza and deliver it himself within 3 and a half minutes. Upon arriving Mike is known for his world famous phrase...
Slang abridgement for "Coffee with Double Cream and Double sugar".
Although attributed to Canadians and popularized by the Tim Horton's chain, the term "double double" actually has its roots in New-York where it was started by writer Truman Capote who thought it more efficient when ordering coffee at a deli.