Steps

• 1

  Make the sauce: In a small bowl, combine the mayonnaise, mustard, horseradish, and Worcestershire and stir until combined. Cover and refrigerate until ready to use.

• 2

  When ready to cook, heat the Traeger with the lid closed to 225°F; this will take about 15 minutes.

• 3

  Shape the ground beef into four 1-inch thick patties and season with the Traeger Burger Rub, using about 1 teaspoon per side of each patty.

• 4

  Place the patties directly on the grill grates, close the lid, and start smoking. The burgers will need to smoke for 30 minutes; about halfway through cooking you'll want to preheat the flat top as described in the next step.

  225 ˚F / 107 ˚C

  00:30

• 5

  When there is about 15 minutes left to the burger smoking time, preheat 2 adjacent zones of the flat top to medium heat, for 8 to 10 minutes.

• 6

  Drizzle or squirt 1 tablespoon oil over the cooktop then spread with a spatula. Add the onions and season with about 1 tablespoon Traeger Burger Rub. Cook, tossing occasionally, until the onions have softened and are beginning to brown, about 7 minutes. Add the balsamic vinegar and cook, tossing, until tender, about 1 minute. Move the onions over to a cool zone until ready to serve. Meanwhile, place the buns cut-side-down on the cooktop until toasted, 30 to 60 seconds, then transfer to a plate.

• 7

  After the burgers have smoked for 30 minutes, transfer the patties to the hot flat top cooktop. Cook, flipping once, for 5 minutes per side for medium doneness. Top each burger patty with a slice of Gouda, cover as with the steam dome (two at a time if necessary) and allow the cheese to melt completely, about 1 minute.

• 8

  To serve, spread the pub sauce on the toasted buns, as desired. Add a burger patty to each bottom bun, top with the balsamic onions, and finish with the top bun. Enjoy!