In one, the cooking juices are poured into a clean pot to concentrate and thicken. In the other, the juices are cooked in the roasting pan to take full advantage of the drippings.
In a separate pot
Begin by pouring the liquid from the roasting pan into a measuring cup. Allow it to settle, then use a turkey baster or spoon to remove the fat.Pour the defatted liquid in the measuring cup into a pot. Place the pot on the stove over medium heat to concentrate the flavor.
To thicken your gravy, combine two tablespoons of arrowroot, corn starch or potato starch with equal parts cold water in a bowl. Whisk vigorously to remove all lumps.
Add this mixture, called a "slurry" in small amounts. Mix well. Be sure to allow time for the slurry to cook in the turkey juices. Otherwise, your gravy will taste starchy.
Continue to stir and boil the liquid, stirring until it reaches the consistency you are looking for. Add more cornstarch, arrowroot or flour if necessary.
In the roasting pan
Start by removing the vegetables, but leave the liquid in the pan. Tilt the pan gently and scoop out as much of the fat as possible with a deep spoon.Place the turkey-juice-filled pan right on the stove and turn the burners to medium.
Pour in about one cup of white wine or chicken broth. Cook gently, scraping the little bits off the bottom of the pan with a wooden spoon until the gravy reaches desired thickness.
If you want a smooth gravy, strain it through a fine sieve before placing it in a heated gravy boat for your guests to enjoy.
