What is “the culinary chops”?

"Chops" is just a slang expression for skill. It derives from the music world (jazz, to be specific), likely (but don't take this as gospel) from a brass player's embouchure in its original incarnation. This would relate it directly to the once-current slang use of "chops" for the mouth or jaws (still heard in the phrase busting [someone's] chops).