Strapping centre-half Sol Bamba gave the 'Bluebirds' a shock 1-0 lead against Maurizio Sarri's side at Stamford Bridge, only for Hazard to then come to the fore and dig his side out of a hole.
That goal sparked wave after wave of Chelsea pressure in response and it eventually told with eight minutes to go until the break as Hazard got his name on the scoresheet for the first time.
It was vintage Hazard, with the Belgian beating his man with a feint after receiving the ball from Olivier Giroud before driving low and hard into the far bottom corner beyond Neil Etheridge from the edge of the box.
Just six minutes later the playmaker struck again. Pedro did well down the left to twist and turn and eventually get a low cross away.
Giroud was heavily involved once again as he cleverly laid the ball of for Hazard first time, allowing the Belgium internation to fire home at the near post with the help of a deflection.