Melt butter in pan over medium heat. Whisk in lots of pepper then flour and poultry seasoning. Cook 2 minutes then whisk in stock and Worcestershire. Raise heat a bit to thicken gravy to lightly coat spoon then add a ladle of the sauce to a bowl with the egg yolks to temper them. Whisk tempered yolks back into sauce to add gloss and viscosity. Cover and turn off heat.
To serve, bring the gravy to a low bubble then whisk in pan drippings from your turkey.