Here is the full list of all 19 Ben and Ed achievements.
Impress 1100 viewers.
Impress 700 viewers.
Collect 100% of all candymeat.
Kill 100 chicken.
Beat all level unharmed.
Kill 50 chicken.
Kill 20 chicken.
Finish the game.
Reunite with your friend.
Beat Hans.
Beat 12 level unharmed.
Beat Hans' second masterpiece.
Impress 200 viewers.
Collect 50% of all candymeat.
Collect 20% of all candymeat.
Beat 5 level unharmed.
Beat Hans' first masterpiece.
Reach a checkpoint in one piece.
Finish the tutorial.