Preheat the oven to 300°F/190°C.
In a large sauté pan over medium heat melt the butter, then sweat the leeks and add the minced sage and thyme. Season with 2 four-finger pinches of salt and some freshly ground black pepper.
Combine the eggs and the turkey stock and whisk or blend to combine.
Combine the sautéed leeks, bread, custard (eggs and turkey stock), and parsley. Toss and set aside for 10 or 15 minutes, pressing down on the bread so that it absorbs the custard.
Butter a baking dish or a cast iron skillet, and pour in the stuffing. Dot the top of the stuffing with extra butter. Cover with aluminum foil and bake 30 minutes; uncover and bake until golden, 15 to 30 more minutes.