Ingredients

• 1 large yellow onion, thinly sliced
• 1 apple, cored and thinly sliced crosswise in rounds (we like Honeycrisp, Rave®, and SweeTango®)
• 1½ lb. ground beef (we used 90% lean)
• 4 plain burger buns
• 4 oz. aged white cheddar, thinly sliced
• Olive oil
• Salt & black pepper to taste
• Optional: condiments

Directions

1. Heat a cast iron skillet over medium-high heat and add onions, olive oil, salt, and black pepper. Once onions begin to soften, reduce temperature to medium-low.
2. Cook, stirring occasionally, for 20-25 minutes. The onions will be soft and tender. If you want a deeper caramelized flavor, continue cooking over low for up to 1 hour total, until the onions become jammy and a dark golden color.
3. Season ground beef to taste with salt and pepper. Form 4 burger patties.
4. Heat a grill or cast iron skillet to medium-high heat. Brush olive oil on grill or skillet to prevent sticking. Cook patties for about 3-4 minutes on the first side and flip when browned. Cook the other side until you've reached the desired internal temperature. Top with cheddar about 1 minute before removing from the heat.
5. Lightly toast buns, then assemble burgers with onions, an apple slice, and any additional condiments.