Answer: A Candy Commercial

Enduring Simpsons character and fan-favorite Milhouse didn’t actually make his first appearance in an episode of The Simpsons. In between the period of time when The Simpsons were an animated short on The Tracey Ullman Show in 1987 and the premiere of the show as a stand alone animated sitcom in 1989, Bart Simpson and Milhouse were featured in a Butterfinger candy commercial.

Long before Milhouse was established as Bart’s gullible and good natured best friend, he served as a foil for Bart in the commercial. The focal point of the commercial was Bart explaining how “Butterfinger” is a food group (along with the sandwich, cow, and jungle food groups) and that Milhouse is at risk of malnutrition because he doesn’t have the Butterfinger food group in his lunch sack.

While the commercial’s premise is silly, it did offer excellent foreshadowing of the relationship between Milhouse and Bart wherein a frequent theme is Bart’s fast talking and precocious ways causing distress and trouble for his naive and easily distressed friend.

Bonus Trivia: Milhouse is named after Richard Milhous Nixon because Simpson’s creator Matt Groening believed that “Milhouse” is the most unfortunate name a child could have.