Slice the brioche buns in half horizontally. Spread a thin layer of softened butter on the cut sides.

Toast the buns in a hot skillet or on the grill until golden brown, about 1-2 minutes. Remove and set aside.

Heat a small skillet over medium heat. Cook the bacon slices until crispy, about 5-7 minutes, flipping occasionally.

Transfer the bacon to a paper towel-lined plate to drain excess grease.

Divide the Kobe beef into 4 equal portions. Gently shape into patties about ¾ inch thick, being careful not to overwork the meat.

Lightly season both sides with salt and pepper. For an optional flavor boost, mix the minced garlic into the beef before forming the patties.

Heat a cast-iron skillet or grill over medium-high heat. Lightly oil the surface.

Place the patties on the hot surface and cook for 3-4 minutes per side for medium-rare (internal temperature of 130°F). Avoid pressing down on the patties.

During the last minute of cooking, place a slice of cheddar cheese on each patty. Cover the skillet or grill with a lid to melt the cheese.

On the bottom half of each toasted brioche bun, spread 1 tablespoon of ketchup.

Layer with lettuce leaves, a slice of crispy bacon, the cooked patty with melted cheddar, and thinly sliced red onion.

Finish with the top bun.

Serve the Kobe beef hamburgers immediately with your favorite side dishes, such as French fries, coleslaw, or a crisp garden salad. Pair with a chilled lager, iced tea, or your beverage of choice.