How to Make It
Arrange bacon in an even layer on a small baking sheet; freeze until frozen, about 1 hour. Transfer bacon to a food processor; pulse until finely ground, 5 to 10 times. Transfer bacon to a large bowl. Add beef, salt, and pepper; combine using hands until fully incorporated. Gently shape into 8 even balls.
Place a griddle or large cast-iron skillet on unoiled grates of a gas grill, and preheat grill to high (450°F to 500°F) until griddle smokes, about 10 minutes.
Working in 2 batches, coat hot griddle with cooking spray; arrange burger balls on griddle. Using a large, flat metal spatula, press balls firmly to flatten to about 3/4-inch-thick patties. Cover grill; cook patties 2 minutes. Turn patties over; cover grill, and cook 1 minute. Place 1 cheese slice on each patty. Cover grill; cook until cheese melts, 1 minute. Transfer to a plate; cover loosely with aluminum foil. Repeat with remaining patties and cheese.
Brush cut sides of buns with melted butter. Place buns, cut sides down, on unoiled grates of hot grill. Grill until toasted, about 1 minute per side.
Place 1 patty on each bun bottom; top with Spicy-Sweet Refrigerator Pickles, desired toppings, and bun tops.