be (as) proud as punch

To be proud of oneself or some outcome, possibly to the point of arrogance, vanity, or boastfulness. The phrase refers to the titular character from "Punch and Judy," a 17th-century comedic puppet show. Sometimes capitalized. I'm proud as punch of the work I've done on the house. It looks so good! Tom's been as proud as Punch ever since he found out he came in top of the class—he hasn't missed a single opportunity to remind us. Well, aren't you proud as punch! I guess the job interview went well.