McDonald's has blanketed America with its restaurants, but opening new locations isn't the only way the fast food superpower can grow.

There's one untapped part of the U.S. market that the chain is now aiming for: the length of time between 2 a.m. and 5 a.m.

Less than 1 percent of total fast food traffic comes in during the "last unconquered frontier" for quick-service restaurants, according to an NPD report cited by Burger Business.

So, what's McDonald's plan?

Transform midnight into the beginning of the morning, extending breakfast into a 10-hour chunk.

It's testing Breakfast After Midnight, which is a menu featuring some of its most popular breakfast items, during late-night, reports Dan Eaton at Columbus Business First.

McDonald's is trying out the menu in Ohio — a very popular fast food test market — but only at restaurants that are open 24 hours. The “Nocturnivore” campaign that's coming with it promotes late-night dining, offering both breakfast and burgers.

The fast food world better watch out. After all, McDonald's breakfast menu is already powerful, and it would be a big win for the chain if it can claim the final part of the day still unconquered by fast food.

The menu includes:

Egg McMuffins

Sausage McMuffins

Hotcakes with sausage

Breakfast burritos

Fruit and maple oatmeal

Hash browns

Juice

Coffee

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