Caramelized Onion Bacon Burger

To caramelize the onions, heat butter and oil in a pot over medium-low heat. Add the sliced onions and a pinch of salt. Cook slowly, stirring occasionally, until deeply golden brown and caramelized. This can take 30-45 minutes.

To make the Dijonnaise, add the egg, white wine vinegar, and lemon juice to a food processor. Blend until combined. With the processor running, very slowly stream in the neutral oil until the mixture emulsifies and thickens into mayonnaise. Transfer to a bowl, stir in the Dijon mustard, and season with salt to taste.

If grinding your own meat, cube the brisket, short rib, and chuck roast and pass through a meat grinder. Otherwise, use pre-ground beef.

Gently form the ground meat into four 1/2-pound patties. Avoid overworking the meat. Press a dimple into the center of each patty with your thumb to help it cook flat.

Season both sides of the patties generously with a mixture of dried rosemary, salt, and black pepper.

Heat a griddle or large cast-iron skillet over high heat. Cook the patties for about 3 minutes per side for a medium-rare finish.

Top each patty with two slices of Gruyere cheese. Place the patties under a broiler for a minute or two, just until the cheese is melted and bubbly.

Butter the cut sides of the brioche buns and toast them on the hot griddle until golden brown and crispy.

Assemble the burgers. Spread a generous layer of Dijonnaise on the bottom bun. Add the cheesy patty, a pile of caramelized onions, sliced pickled jalapeños, and two slices of crispy bacon. Top with the other half of the bun and serve immediately.