Flour makes gravy thick. Cooling gravy gets very thick too. However, what has been said is that floured gravy that is cooked at a high heat for a long period of time will eventually lose its thickness. The key is that the floured gravy is cooked at a high heat for a long time. Something happens that results in a breakdown of the flour's ability to keep the gravy thick. If you normally don't heat your gravy at a high heat for extended periods of time, you would never encounter this situation. It's similar to the idea that browned flour, such as is used for making a traditional dark roux, doesn't have the thickening power of a lighter colored roux. So boiling a thin, floured gravy may not result in a thicker gravy. Not unless it is boiled enough to actually reduce the liquid quite a bit. "Sauces thickened with starches should be reheated carefully, as they will lose some thickening ability if reheated to a full boil."

I would not add smoked juices to the gravy either. Not everyone likes too much of that flavor. I just assemble my stuffing and then bake it the next day. I even tried the make-ahead mashed potatoes this year. Less mess and dishes on turkey day. Just remember to take the dishes out and try to bring them to room temp a few hours before they go in the oven or add cooking time to the recipe. It might be cold in the middle if you use the original cooking time. I have time change notes on all of my make-ahead recipes.

I think this is good gravy, I do not use the giblets or the neck, because I buy the turkey parts separately to make this gravy. Cook's Country Make-Ahead Turkey Gravy Makes about 2 quarts For more flavor, after roasting the turkey you can skim the drippings from the pan and add them to the gravy just before serving. It's best to discard the strong-tasting liver before using the giblets. This recipe makes enough to accompany a large turkey and still have plenty for leftovers. 6 turkey drumsticks, thighs, or wings reserved turkey giblets reserved turkey neck 2 carrots , chopped coarse 1 head garlic , halved 2 ribs celery , chopped coarse 2 onions , chopped coarse Vegetable oil spray 10 cups low-sodium chicken broth 2 cups dry white wine 12 sprigs fresh thyme 1/2 cup all-purpose flour Table salt and ground black pepper 1. Adjust oven rack to middle position and heat oven to 450 degrees. Place giblets, neck, drumsticks, carrots, celery, onions, and garlic in roasting pan, spray with vegetable oil, and toss well. Roast, stirring occasionally, until well browned, 1 to 1 1/2 hours. 2. Transfer contents of roasting pan to Dutch oven. Add broth, wine, and thyme and bring to boil over high heat. Reduce heat to low and simmer until reduced by half, about 1 1/2 hours. Pour through fine-mesh strainer into large container (discard solids), cover stock with plastic wrap, and refrigerate until fat congeals, at least 2 hours. 3. Using soup spoon, skim fat and reserve. Heat 1/2 cup fat in Dutch oven over medium-high heat until bubbling. Whisk in flour and cook, whisking constantly, until honey colored, about 2 minutes. Gradually whisk in stock, bring to boil, reduce heat to medium-low, and simmer until slightly thickened, about 10 minutes. Season with salt and pepper. (Gravy can be refrigerated for up to 3 days or frozen for up to 2 months.) Reheat gravy in saucepan over medium heat until bubbling.

It will turn back to liquid as it heats, no worry. The gelatinous nature just means that it will be rich, as home made stock should be. The thin layer on top is fat. You can scrape it off. Don't worry if you scrape a little stock off with it, when you heat it before mixing in the flour, it will evaporate and leave it's flavor behind. The darker layer at bottom just contains the "sediment"...again, don't worry. Were you trying to make clear broth, there are things you could do to remove the sediment, but for gravy there is no need. Just in case...if your gravy should form lumps, despite vigorous whisking, just use a stick blender or if you don't have one, a regular blender, to puree them out. The gravy will likely thicken more if you refrigerate it, so when you reheat, be sure to do so over a fairly low heat and stir occasionally so you don't scorch it after all your work.