Sprinkle the turkey pieces with salt and pepper.
1-2 pounds bone-in turkey pieces, Kosher salt and freshly ground black pepper
Heat the canola oil in a large Dutch oven or saucepan set over medium-high, then brown the turkey pieces for 3-5 minutes on each side.
4 tablespoons canola oil
Add the carrots, celery, and onion. Cook another 5 minutes, turning once, until vegetables have begun to caramelize and have some golden brown color.
2-3 carrots, 2-3 ribs celery, 1 yellow onion
Turn the heat down to low, cover, and cook for 15-20 minutes. Stir every 5 minutes.
Scrape the pan, while slowly adding the sherry or wine, to deglaze the pan. Continue scraping the pan and add the turkey stock, stirring continuously.
¼ cup dry sherry wine, 8 cups turkey stock
Add the herbs, turn the heat back up to high, and bring the broth to a boil. Reduce the heat back to low and simmer, uncovered, for 30 minutes. Skim excess foam off the surface as needed.
5 sprigs fresh thyme, 8 stems fresh parsley, 2 dried bay leaves
Pour the broth through a fine-mesh strainer over a large heat-resistant bowl. Shred the turkey meat from the bones, and (if desired) reserve ¼-½ the meat for the gravy. Freeze the remaining meat, in a freezer bag, for later use. Pour the broth back into the large saucepan, and bring it to a low boil.
To make the roux, melt the butter in a medium saucepan set over medium-low heat and whisk in the flour. Cook, stirring continuously, until the flour mixture is fragrant and nutty brown, 10-15 minutes.
½ cup unsalted butter, ½ cup all-purpose flour
While whisking vigorously, slowly add 2 cups of the hot broth to the roux (flour/butter mixture). Whisk until the mixture is smooth and there are no lumps. Whisk the roux mixture into the simmering broth in the large saucepan.
If making gravy with the reserved turkey meat, add it to the gravy now.
Season the gravy to taste, and bring to a boil. Reduce the heat to low, stirring often, and keep at a simmer until gravy has thickened or about 20-30 minutes.
Cover and set aside to cool to room temperature.