This is actually really easy to obtain, just enter a free practice session and select the following setup:
Circuit - Nordschleife
Car - Mclaren P1
Track condition - Clear (not mandatory but it helps)
As soon as you leave the pits just turn around and go the wrong way, turn left and through the chicane, than accelarate down the hill and up the other side, follow the straight all the way along and you should easily reach the 333km/h (207mph) needed.