It is basically a regular Krabby Patty, but it costs twice as much and is only served to executives.
Role in episode
Patrick wants an Executive Treatment, but Squidward tells him that only executives can eat it and that SpongeBob wears a different tie when delivering the patty to a customer. Patrick pays twenty dollars for a tie and business glasses to look like a businessman and be able to order it. This plan backfires as real executives mistake Patrick as an executive as well and bring him to an executive meeting, preventing Patrick from eating his patty. Squidward attempts to throw it away, but Mr. Krabs stops him from throwing away a perfectly sellable sandwich.
After Patrick is discovered as a fake executive, he is sent to jail. While visiting, SpongeBob learns that Patrick is in charge of the laundry room, which means that he is a real executive. As such, SpongeBob feeds the Executive Treatment to him by shoving it through the prison phone.