Up to a week in advance, make the caramelized onions.

Preheat oven to 375°F.

Line a rimmed sheet pan with parchment or foil.

To make the bacon weave, start by laying four bacon slices next to each other, long sides touching, in the middle of the pan.

Then, one by one starting at the top, lay each of the remaining pieces crosswise. Weave the first piece over, under, over, under the original slices. Weave the second piece under, over, under, over, etc.

Bake bacon until done to your liking — 15 minutes plus, depending on the thickness of the cut.

Drain on paper towels.

When cooled enough, cut weave into four squares.

Meanwhile, form four burger patties from the ground beef.

Sprinkle generously with salt and pepper immediately before cooking. You can grill the burgers or cook in a cast-iron pan

To grill, prepare a hot side and a cooler side of the grill with a little oil on the grates. Start burgers over direct heat, flipping once, to form a nice crust on both sides. This should take about three minutes per side. Transfer burgers to indirect heat to cook through to your liking (125°F for medium-rare, 130°F for medium on an instant-read thermometer).

For cast iron, preheat a 12-inch cast iron pan over high heat until very hot. Set burgers into pan. Cook on high heat to form a crust on both sides, flipping once, then reduce heat to medium and continue cooking according to internal temperature instructions above.

Let burgers rest for 5 minutes before assembling.

To assemble the burgers, toast the buns for a minute or two if you like, then layer on a burger patty, followed by a slice of blue cheese, some caramelized onions, bacon weave, shredded lettuce, and ketchup. Close buns and serve.