This week, McDonald's debuted the Cheddar Bacon Onion Sandwich (CBO) in stores nationwide. It is available on a burger or grilled chicken. The sandwich consists of two new premium toppings of white cheddar and grilled onions, combined with McDonald's existing hickory-smoked bacon. It is topped with a mustard sauce.

While the CBO is a new item, it's actually been around in very similar forms such as the Clubhouse Angus with smoky dijon and the English Pub burger.

McDonald's focus on white cheddar is further proof that there might be an increased focus on the cheese as a premium ingredient in fast food restaurants. Earlier this week, Burger Business reported on white cheddar's popularity as a specialty burger topping based on rumors about a not-yet-released Burger King Whopper with white cheddar.

But the idea that there's anything very special about white cheddar may be unfounded. There's not actually much of a difference between white cheddar and orange cheddar. In fact, orange cheddar is usually just white cheddar dyed with annatto. So that supposed "premium" taste you are having is really not so premium at all.

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