The Brotherhood's main target seems to be the Emperor himself, so of course, a little bit of preparation is needed. Among other minor preparations, the player needs to disguise himself as a chef that's been named to cook for the Emperor. After learning the chefs' identity from a not-so-willing source, the Dragonborn has to make the first choice of this quest. Well, actually, not a choice per se, but a choice in how to inform the informant that he's dead. The best option is to not make any fuss, remain silent as he pleads for his life and then follow him and complete the kill.
After hiding the body with the utmost discretion, the player has to go to the Nightgate Inn, where he must kill Balagog gro-Nolob, the orc chef. It doesn't matter if the player chooses to do it by day or by night when the target is asleep. To acquire the bonus, however, his body must be hidden. You know, for obvious reasons.
To finish the quest, the player has to report back to Festus Krex. It's not that this quest is very entertaining, but it's the final step in the biggest and boldest attempt of all, killing the Emperor. Now don't tell me that's not exciting!