In general, food is not kept in any particular sequential order. The stomach has a lot of smooth muscle which churns the food, very rapidly erasing any "order" to the food. Beyond that, the stomach digests "the food in the stomach," in parallel. Whatever is in it, it digests.
Now, in general, food eaten earlier will digest into chyme (the digested slurry which enters the intestines) sooner, but that's a very general pattern and doesn't account for any differences in how long it takes to digest various types of foods.
I don't have any sources to back this next claim up, but I do believe that if you were to chew some steak poorly, and then follow it up by more steak chewed properly, the later steak would actually digest first because it would take less mechanical processing in the stomach to get the digestive enzymes to where they need to be to work.