To make pie dough: Combine flour and salt in the bowl of a food processor and pulse a few times to mix. Drop in the cold butter a few chunks at a time and pulse 4-6 times. Add the duck fat and pulse a few more times until the mix looks like polenta.
Add 3-5 Tbsp water one at a time and pulse just until the dough begins to come together. Remove from the food processor and form into a flat disc. Dust with flour and wrap in plastic wrap. Place in the refrigerator for 1 hour.
When ready to cook, start the Traeger grill on Smoke with the lid open until the fire is established (4 to 5 minutes). Set the temperature to High or 450 degrees F and preheat, lid closed, for 10 to 15 minutes.
Place game bird pieces directly on grill grates and grill for about 15-20 minutes or until browned nicely. Take the game bird pieces off the grill, set aside and salt them.
In a shallow cast iron pan, lay out all the herbs, spices, potatoes, carrots and wine. Add a bit of salt. As the game bird pieces brown, lay them in the cast iron pan skin side up.
When everything is in, add the chicken stock up to the level of the skin on the game birds and place directly on the grill grate and cook uncovered for 15 minutes. Drop the temperature to 350 degrees F and cook for another 30 minutes.
Remove and let everything cool leaving the grill on. Remove the bird pieces and pick the meat off the bones then return to the stew tossing the bones.
To make the pie: Remove pie dough from the fridge. Roll out the pie dough large enough to cover the top of the cast iron pan. Fill the cast iron pan with the stew – leave about 1/4 space from the top, then cover with the crust. Cut slits in the top of the pie to let the steam escape.
Brush the crust with egg yolk and return to the grill. Bake for 45 minutes or until the crust is golden brown.
Remove and let stand 10-15 minutes before serving. Enjoy!
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