Heinkel 111 for the delivery.
My spies tell me that the HE 1800 Satan bomb was the largest bomb delivered by the Luftwaffe. This somewhat contradicts the information in the previous post which indicates a 2,000kg bomb.
Here are a couple of links, one in German, which you might find interesting.
1800 Kilo schwer, Spitzname "Satan": Hitlers Superbomben gefunden - Frankfurt - Frankfurt - Bild.de
SC 1800 Satan German HE bomb