Place it at the peak of a food or chat argument, just after the question that sets it up, then follow it with Bruh for a deadpan comedown or Scream Meme when the reaction should escalate instead. Keep it as the centre of that short sequence.
About this sound
This clip is one voice stretching the word mustard into a long, wobbly shout that lasts about five seconds, with the middle held far longer than the ending. It feels deliberately silly and over the top, like someone refusing to say a normal word normally, and it lands best as a sudden burst of nonsense in the middle of an otherwise ordinary exchange.