Place the beef into a large mixing bowl and then add onion, A.1. sauce, and all of the seasonings to the meat.
Mix the ingredients together well.
You will then want to slice the cheese into small slices. Then make six thin even patties and then form an indentation for the cheese in the middle of three of the patties.
Add the cheese to the three indented patties and cover with the other three remaining patties, surrounding all of the cheese with meat and clamp the edges together, you will now have three large patties instead of six with cheese in the middle of them.
Place the patties on the grill or grill pan and cook the first side for 5 minutes.
Flip the burger over and grill for an additional 5 minutes, you may repeat these steps to each side for a more well done burger depending on your preferences.
Place the burgers on a sesame bun and add your favorite condiments.