Smashing Patty with Confidential Sauce

Output: four sandwiches

One tablespoon of olive oil is required.

2 cups of finely sliced onion from 1 big onion

Six tablespoons of unsalted butter, divided Garlic powder and kosher salt

ketchup, 2 tablespoons

1 and a half pounds of lean ground beef

2:1 Worcestershire sauce

8 rye bread slices

Onion powder, 1/2 teaspoon

Roughly eight ounces of Swiss cheese, sliced

Instructions:

Olive oil should be heated in a big pan over medium-low heat. Twenty to twenty-five minutes after adding the sliced onions, caramelize them by cooking them, turning regularly, until they are very brown. Add little salt and pepper to taste.

A cast-iron skillet should be heated over medium-high heat while you wait. In a heated pan, melt 2 tablespoons of butter.