In a large bowl pour in all of the Turkey Broth/Stock (Could also be Chicken Stock) and marinate the uncooked Turkey Legs overnight, or at least 3 hours, in the refrigerator.
After 3-8 hours in the refrigerator, take a large roasting pan with a wire rack, remove the refrigerated legs from the bowl of broth---use tongs and place directly on the roasting rack/pan. Sprinkle generous amount of salt, black pepper, and onion powder on each leg. Spread foil across the top of the roasting pan to keep the legs covered while roasting in a pre-heated 350F oven.
Meanwhile, melt a stick of butter in a saucepan---until it's liquified.
8 legs usually take about 1hour and 45 minutes to fully cook. The legs need to be turned/flipped with tongs, basted (brushed with the melted butter) and then re-seasoned with just the onion powder and black pepper--- every 20 minutes during roasting.
Turkey legs are usually done after insterting a meat thermometer that registers 175F in the thickest part of the leg, however, they do keep cooking even after they're removed from the oven.
The cooked turkey pan juices and drippings are usually used to flavor gravy and stuffing.