Preheat the oven to 350°F and the grill to medium heat.
Cut the cooked bacon strips in half crosswise and arrange on a baking sheet. Warm the jelly until spreadable then brush on each piece of bacon to coat. Bake the bacon in the oven until the jelly is set, about 5 minutes. Remove and set aside.
Divide the ground beef into 18 portions and shape into patties slightly larger than the buns to allow for shrinkage; don’t overwork the meat. Press the center of each patty slightly so burger doesn’t puff during grilling. Season the patties on both sides with salt and pepper. Grill the patties on one side for 2 minutes, flip, then top with ½ ounce (about 1 tablespoon) of the blue cheese. Continue grilling until burgers reach an internal USDA requirements of cooking ground beef to 160 degrees. Remove and let rest 3 minutes. Meanwhile, butter and toast the buns.
For the topping, in a medium bowl, mash the garlic with the salt. Whisk in the olive oil, sugar, lemon juice and mustard, then add the arugula and onion and toss to coat.
To assemble the sliders, place a blue cheese-topped burger on toasted bun bottom. Top with 2 strips of glazed bacon and ¼ cup arugula salad; add the top half of the bun.