To make the gravy, in a skillet over medium heat, whisk together the beef broth and 3 tablespoons of the flour. Once this begins to thicken you can stir in the sour cream and the Worcestershire sauce. Bring this to a simmer until you reach your desired consistency. If the consistency seems to thin, you can add the additional flour, 1/2 tablespoon at a time, Be sure to whisk the gravy to prevent sticking and burning..
Serve your turkey meatballs with the gravy poured over it.
As mentioned, You could use already prepared turkey meatballs, which you can find online.
I also mentioned that flour is usually used in a meat based gravy such as the one in this recipe. However, flour has carbohydrates in it.
We are using three tablespoons of flour which nets out at about 18 carbohydrates or three carbs per serving.
As a result of the carbs, you could use an alternative thickener instead.
You can find a thickener for gravy that is low in carbs online. I would suggest that you find one that measures 1:1 with flour in volume, or close to it if possible.
See post for details.