I would try Gravy Master. It is all veggie seasonings, and caramelized
sugar. It is not as salty as Kitchen Bouquet, which almost ruined a
meal when I used it instead of Gravy Master.

One caveat: I made turkey burgers and didn't tell it wasn't ground
Beef. When people wanted theirs on the rare side, we did cook them
that way, and I held my breath that no one would get ill. They didn't,
but I vowed to use only beef when it was guests for whom we were
cooking. And I wouldn't eat Turkey burgers any way except fully
cooked. YMMV.

The meal I almost ruined was Black Diamond Steak. Skirt steaks
marinated in: Gravy Master, onion powder, garlic powder, paprika,
salt, pepper, and a little cayenne. Let them soak for 6 or so hours
then do them on the grill. This is a real favorite at our house. The
name comes from the pieces of sand washed glass that are sold & found
on the beaches at Cape May NJ. They are called Cape May Diamonds. The
restaurant we had the Black Diamond Steak at was in Cape May. Steaks
will be black on outside but pink inside, according to how long you
cook them.