Mix the ground chuck, salt, chili sauce and oregano together lightly. Split the English muffins in half. On each half, spread the meat mixture about 1/2 inch thick. Place several slices of onion on top of meat. Cut the pieces of cheese in half and crisscross them on the meat and onion mixture. 
Place in a 400° F. oven for 8 to 10 minutes or until cheese is melted and bubbling. 
Serve immediately.