Season the burgers generously with salt and pepper in a bowl and mix thoroughly.
Roll the burgers into balls first, then stuff the butter cubes in the middle. Make the cubes about ½ as small as pictured.
Shape the burgers with clean hands into burger patties. Make sure the butter is completely covered by the meat.
Get all the other ingredients ready to go. Fry the bacon until crispy and then cook the mushrooms in the bacon fat. Make the mac sauce. Slice the cheese, pickles, tomatoes, and pick the lettuce. Have everything ready to go so when the burgers are ready, you are ready.
Fire up the BBQ and grill the burgers over medium high heat. Quarter turn once, then flip, then quarter turn again. This takes about 10-15 minutes in total.
Once the burgers are almost ready add the cheese and bacon. Cook to 160°F/71°C.Cut the burger buns in half, brush them with some butter and give them a quick toast on the grill.
On the top of the bun add the sauces, lettuce, tomatoes and pickles. On the bottom put the burger with the cheese, bacon and top with mushrooms. You may need to use a toothpick to hold these together. Enjoy!
Notes
The burgers need a good amount of seasoning. If you're not sure how much to add then add some salt and cook a tiny burger to taste it first. Season to your liking.Once the burgers are seasoned they need to be cooked right away. The salt will start to cure the meat. If you want to save some for later you can form them and freeze them. When working with raw meat always wash your hands with soap before touching something else. To avoid cross-contamination and food poisoning never use anything that touched the raw meat with the raw ingredients.