Is the chicken chop a local Malaysian creation: I’m not able to provide a history of how it came about, but it may have something to do with the Hainanese in Malaysia. No one outside of Malaysia or Singapore seems to know what the heck a chicken chop is. It is not even to be found on Wikipedia. Pork or lamb chops yes but chicken chop? Only in Malaysia.
My first chicken chop experience was definitely in the 1950's at The Tanjung Club in Muar. Later on in the 60's I have eaten this superb dish at rest houses, railway restaurants, army messes and some Chinese restaurants.
Today there are at least three varieties . One is the dry type which is quite rare. The other two types come with some thick gravy. The gravies are of two types. One is mainly tomato ketchup and reddish in color. The one that I would plainly say is the more "original " Hainanese Chicken has hints of taste from the HP sauce and Lea & Perrin's Worcestershire sauce. The chicken chop as I remember it from the rest houses and army camps of colonial days had this sort of brownish gravy. The one that is more easily found these days is the tomato ketchup variety.
Whatever it is, there are two halal places that I know of in Seremban that serve that "original" variety with the brownish sauce ( see picture) .....The Royal Sg. Ujung Club and Jayamas Resaturant.