In a small bowl, combine all the spices for the rub.
Trim your sirloin of any excess fat and silver skin. Rub the roast with oil and then coat well with the rub. Press it firmly into the meat, and then allow the roast with the rub to come to room temperature while you heat your grill.
Preheat the grill to high, about 500°F, or warm your sizzle zone side burner.
Sear the roast on all sides and then carefully transfer it to a roasting pan with a rack that keeps the roast off the bottom. Reduce the grill’s temperature to medium, about 350° to 375°F. Pour the 2 cups of broth into the roasting pan. Do not pour it over the beef, you don’t want to wash off the rub.
Place the lid on the roasting pan and grill roast over indirect heat for 35 to 50 minutes, until a meat thermometer reads 125°F for medium rare.
Once the roast is on the grill beat the eggs together with the milk in a bowl. Add the flour for the yorkshire pudding then set aside. Divide the butter up between all of the cups in a muffin tin and melt it on the grill. Distribute the batter evenly between all of the cups and bake for 30 minutes. Hopefully about the same time your roast will be done.
Allow the beef to rest on a cutting board, covered, while you use the drippings to make a perfect gravy.
Slice the meat and serve with yorkshire puddings and gravy, oh and some vegetables I guess.