Bring a large pot of water to a boil. Add in the egg noodles, and cook until tender, about 6-8 minutes. Drain and set aside.

While noodles are cooking, heat oil over medium-high heat in a large skillet. Add in onions, and cook until onions are translucent about 2 minutes.

Add in ground turkey, allspice, nutmeg, and salt and pepper, and cook (while breaking up meat with a wooden spoon) until meat is no longer pink and well browned about 8-10 minutes.

Transfer meat to a bowl, cover and set aside.

Return the skillet to the stove, and melt the butter over medium-high heat. To make the sauce, first, make the roux. Melt butter in the skillet. Whisk in flour until lightly browned, about 1-2 minutes. Gradually whisk in beef broth and cook, whisking constantly, until slightly thickened, about 2-3 minutes. Stir in sour cream; season with salt and pepper, to taste.

Pour gravy sauce over the turkey and stir well. Plate the noodles and top with about 1/2 cup of the turkey and sauce.