Satire runs on one big comparison. Most writers make the comparison once, get the laugh and move on. The ones who make you laugh out loud keep going, until the comparison starts telling the truth on its own.
From this week's drop
The Prunes had been plums once.
Then they had been appointed, and set out in the sun, and left there for life. Now they were dark and wrinkled and dense with everything that had been concentrated out of them, and they sat in a row in their black robes with their hands folded, nine dried fruit who could not be removed, and very regular in their habits.
All nine of them were men. All nine had been appointed by men. All nine were certain this had nothing to do with anything.
From A More Perfect Fruit Union, Season One, Episode Four: “In the Common Language of the People,” by Gray I. Rony.
Why it works
Old judges as prunes is a joke anyone could make. Gray doesn't stop at the joke. He asks what actually happens to a plum to turn it into a prune, and every step lands on the court. Appointed. Set out in the sun. Left there for life. Dark, wrinkled and dense with everything concentrated out of them.
Look at “who could not be removed.” It's a fact about lifetime appointments and a fact about dried fruit at the same time. Then the paragraph ends on “very regular in their habits,” a prune joke in a black robe. You laugh first, and a second later you notice it's also true of any institution that never changes.
The next paragraph pushes once more and turns serious. Three sentences, each starting “All nine.” The fruit falls away, and what's left is the point.
That's the rule: once you've found your comparison, interrogate it. Every true detail of the object that maps onto the target is a joke that also makes an argument.
Try it
Pick something you want to poke at: an office, a committee, a family holiday. Choose one object to stand for it. List five true facts about that object. Write a paragraph where each fact is also, quietly, a fact about your target, and end on the funniest one.