Directions
- Preheat your grill to 300°F.
- In a large bowl, mix together the ground beef, ground pork, eggs, BBQ sauce, and BBQ Rub until combined. DO NOT over mix as this will cause the meat to be tough after cooking. Split the mixture into two equal parts.
- Melt the butter in a pan over medium heat and sauté the onions and mushrooms until golden.
- In a cast iron pan, flatten one half of the meat mixture into the bottom, taking care to work meat slightly up the sides of the pan. Sprinkle in half of the cheese, evenly. Pour in onion mixture and top with the rest of the cheese.
- On a clean work surface, mold the second half of the meat mixture into a circle and place over the filling in the cast iron to complete the burger. Make sure that the top and bottom meat patties are secured together so that the filling cannot be seen.
- Place the cast iron pan in the grill and smoke for 1 hour, or until the internal temperature reaches 160°F. Then, increase the grill's temperature to 425° and open the sear plate. Flip the burger out of the cast iron pan onto the grates and sear each side for 5 minutes, to get those beautiful grill marks.
- To serve, make one enormous burger, or you can cut it like a pie into slices to be served on regular hamburger buns with your desired condiments.
