To prepare the meat, unwrap the bison sirloin or roast and pat it dry with paper towels. Place bison on a cooling rack over a cookie sheet. Refrigerate for at least 4-6 hours (or even overnight) to allow the meat to air dry. This reduces the moisture in your ground meat and allows for a burger that is not too wet and sloppy; they tend to fall apart.
Set up your meat grinder according to the manufacturer’s instructions. Cut the bison sirloin into 1- 2- inch (2.5-10cm) chunks. Chop up the beef fat. Grind the bison meat and the beef fat together. When all the meat has been ground once, give it a quick stir or mix and then grind it again. Place ground meat back into the refrigerator and allow it to rest.
To make the Blackberry Whiskey Compote, combine blackberries, pear, honey and whiskey in a small saucepot. Add in the sprig of fresh sage and a grind or two from your pepper mill. Heat over medium to medium-low heat, stirring occasionally, until the mixture reaches a low boil. Simmer for 10-15 minutes, stirring occasionally, until the mixture is slightly thick. Remove from heat, remove and discard spring of sage and season to taste with a little salt. Set aside.
Set your EGG for direct cooking at 400°F/204°C. Remove grilling plank from water and pat dry with paper towels.
Remove bison from refrigerator. Season the meat liberally with a little salt and black pepper. Scoop the meat (approx. 3 oz/85g) and firmly but gently pack the ground meat into the scoop. Unmold the little ball of meat and place on grilling plank, flat side down. Repeat with all meat. You should be able to get about 12 small balls onto each plank. Squish ‘em a little if you must or grab a second plank. Never buy just one, always have a backup!
Place plank onto hot grill. Close dome and let bison balls plank cook for about 15-18 minutes, until the burgers are cooked to an internal temperature of 145°F/63°C, medium doneness. You don’t want to overcook these burgers as they will get dry and tough. They are much better moist and juicy. Just before the burgers are done, sprinkle the caraway Gouda cheese evenly over top of them. Close dome for a minute or so until the cheese is melted.
Warm the rolls, then take one and tear it open. Spoon in a little Blackberry Whiskey Compote and add a burger. Repeat and serve immediately.