Butter-Charred Beef Burger with Caramelized Onions

Method

1. Preheat grill or skillet to medium-high heat.
2. Form ground beef into 4 equal patties, season with salt and pepper.
3. Melt butter in a pan, add onions, and caramelize over low heat for 15-20 minutes.
4. Cook patties for 3-4 minutes per side for medium doneness.
5. Place cheese on top of patties during the last minute of cooking.
6. Toast buns slightly if desired.
7. Assemble burgers with lettuce, tomato, caramelized onions, and balsamic vinegar.
8. Check that the ground meat reaches 71°C (160°F) throughout before serving.