Add giblets to a large heavy bottomed skillet. Note: if you are using a stainless steel skillet, I would add about a tablespoon of oil to the skillet first.
Then add sage, rosemary, thyme, parsley, chopped onions, lemon wedges and chopped tomato. Cook on a medium low heat for about 10 minutes, stirring occasionally.
Add the 3 cups of turkey drippings (that have been combined with chicken stock) and bring to a slow rolling boil. Turn down the heat and allow it to gently cook for 30 minutes.
Pass through a sieve (strainer) to remove all the large ingredient bits, leaving just the gravy.
Taste and add salt and pepper to your preference. Add to a gravy boat and serve warm with your meal.
Notes
You can use a fresh onion and and fresh lemon wedges if you do not use them in your turkey.
If you do not have enough turkey drippings add chicken stock to compensate.