The Best Hamburgers Ever - cooking recipe

Ingredients

2 lbs ground chuck
1 lb ground sirloin
3 tablespoons steak sauce (I use A1)
6 extra-large egg yolks
1 1/2 teaspoons kosher salt
3/4 teaspoon ground black pepper
4 tablespoons cold butter
12 hamburger buns

Preparation

Mix meats, steak sauce, egg yolks, salt and pepper with fork (do not over-work).
Form mixture into 12 balls.
Put a thin slice of butter in the middle of each ball, then flatten into patties (make sure butter is completely surrounded by meat).
Cook for 3-5 minutes per side until done.
Remove to plate, cover with foil, and allow to rest for 5 minutes before serving.