Ingredients
Equipment
Method
- Chop the onion into thin slices and melt butter in a skillet over medium heat. Cook the onions slowly, stirring occasionally, until they turn deep golden brown and smell sweet, about 15 minutes.

- While the onions cook, shape the ground beef into four equal, thick patties, making a slight indentation in the center of each to prevent bulging. Use your hands or a burger press for even rounds.

- Preheat your cast-iron skillet or grill over medium-high heat until hot. Place the patties on the surface and cook for about 4 minutes per side for medium, flipping carefully with a spatula. Use a meat thermometer to check that the internal temperature reaches 71°C / 160°F.

- While the burgers cook, split the buns and brush the cut sides with melted butter. Toast them in a separate pan or under a broiler until golden brown, about 2 minutes.

- Once cooked, transfer the burgers to a plate and let them rest for 2 minutes, allowing the juices to redistribute for maximum juiciness.

- Spread a thin layer of spicy mustard on the bottom buns. Place a burger patty on each, then top with a slice of cheddar cheese and a generous spoonful of caramelized onions.

- Lay a slice of pumpkin or orange cheese on top of each burger, then cover with the toasted top buns.

- Using a sharp knife, carve jack-o'-lantern faces into the top buns, creating spooky and festive designs that will glow when the burgers are served.

- Serve the burgers immediately while hot, with your favorite fall sides like crispy sweet potato fries or a fresh autumn salad.

Notes
For an extra spooky touch, add small edible eyes or other decorations to the carved faces. Be cautious when carving hot buns to avoid burns. Feel free to experiment with different cheese colors for more seasonal flair.
