01 -
Put onions with butter in pan over medium heat covered for 5 minutes, then keep stirring now and then on low for 30-35 minutes until they turn deep brown. Add vinegar to loosen bits from pan
02 -
Make 3 burger patties and add salt and pepper right before they hit the pan. Warm up your griddle to 375-400°F
03 -
Add oil and cook each patty about 3 minutes on both sides
04 -
Spread butter on bread pieces and brown them on the griddle for 1-2 minutes each side
05 -
Layer cheese, browned onions, and a burger patty on each toasted bread slice. Complete the sandwich and dig in