*Optional* Soak two handfulls of cedar wood chips before starting. Wash and peel your potatoes. Boil them until they’re done, pierce with a fork or knife, if they offer no resistance and then slide right off, they’re ready. Drain the potatoes and mash them with the butter, dill and garlic. Salt to taste. Set aside.
In a large skillet, brown the beef with the steak spice. Drain 2 to 3 tbsp. into a saucepan for making the gravy, and return the beef to the heat and add the onion, garlic and vegetables.
Make a paste with the flour and the beef drippings, then slowly add the beef broth until you have a satisfying gravy, stirring the whole time. Add the sriracha.
Preheat the grill to 350°-400°F. Prepare for indirect grilling.
Spray a large pie plate, or at least six-1 cup-oven safe dishes, with cooking spray. Fill the dishes ¾ of the way full with the beef mixture. Add the gravy and then top with mashed potatoes.
Place the pie plate over the “off” side of the grill and grill bake the shepherd’s pie for about 30 minutes, or until the top is crispy and golden.
*Optional* Fill a Stainless Steel Smoker Tube
with the soaked wood chips and when you place your shepherd's pie on the "off" side of the grill, place the Smoker Tube on the "on" side of the grill to smoke while the shepherd's pie bakes.