The expression is "mince meat."
"vitamins, minerals and proteins," if you wish to emphasize that the combination of beef and pork provides a greater variety of nutrients
"These cutlets" are what you start with, i.e., small portions of solid meat. They may often be served as such, but once you run them through the meat grinder, they are no longer cutlets.
I'd say mince meat is like a relish, and would be considered part of the "trimming," and not something to be served alone, "with or without trimming."
Your bit about the grinder plate is important, and clear to anyone who's used a meat grinder; but it doesn't read well, and would sound mysterious to the uninitiated. Perhaps, "the grinder plate which is designated for medium grinds." You need to make it clear that a selection of plates is provided.
(My mother made her own mince meat for use in pies. Terriffic! You can buy it in the store in jars or cans.) I seem to recall that British mince meat is a bit different. I could be wrong.
You neglected to mention the spices, which are very important.
Best wishes, - A.