I'm lovin' it: McDonald's all-day breakfast is here

It's finally here.

For the first time in 43 years, Egg McMuffin fans are now able to gobble down the breakfast sandwich at whatever time of day they desire.

Starting Tuesday, more than 14,300 McDonald's restaurants in the U.S. will be offering breakfast all day.

While McDonald's started testing all-day breakfast in a few places in March, the nationwide push is aimed at boosting sales, which have been on the decline for seven straight quarters.

But before you think all your breakfast dreams will be fulfilled, here's what you can and can't order -- as the exact menu will vary in different markets.

In most markets, you can order a sausage burrito, Fruit 'N Yogurt parfait, Fruit & Maple oatmeal, hash browns, hotcakes and hotcakes with sausage.

But for example, in markets that serve sausage McMuffin with egg you can't get the Egg White Delight or the steak, egg and cheese McMuffin, but you can get an egg McMuffin, sausage McMuffin with egg or a sausage McMuffin.

Or in markets that offer biscuits, you can't order the "southern style" chicken biscuit, but you can order a bacon, egg and cheese biscuit, sausage biscuit with egg or a sausage biscuit.

The company said core items like the Big Mac, McNuggets and fries will still be available at all of its locations.

To launch the all-day breakfast menu, franchisees have needed to install separate griddles and train staff on how to handle breakfast orders simultaneously with lunch and dinner. Still, McDonald's insists that franchisees supported the decision to serve pancakes and egg sandwiches all day long.

McDonald's has been struggling to turn around slumping sales with new strategies to respond more quickly to trends and to cut costs. The company plans to close about 700 stores this year and will shut down more stores than it opens in the U.S., something it hasn't done since at least 1970 and possibly in its entire corporate history.

From Zohreen Adamjee:

McDonalds customers are lovin' it.

Starting Tuesday, breakfast will be served around the clock. The area supervisor at the East Pasadena store hundreds have already ordered breakfast after 10:30 Tuesday morning.

Some customers told FOX 11 they normally wouldn't be here at night, but they were craving Egg McMuffins and hashbrowns. For the first time, they didn't have to wait until 5 a.m. to get them.

Analysts suspect McDonalds is trying to pick up recent slumping sales with the move. It's a move many customers have already shown they're hungry for.

"Some of the other fast foods do serve 24 hour breakfast like Jack in the Box and people work different hours and they want to have different food at different times. So when there's breakfast available...it's a good thing," said customer Ranjit Vishwanath.

There are a couple items like the deluxe big breakfast and biscuit sandwiches that are not included on the 24-hour breakfast menu in the L.A. area. Customers have to come between 5 a.m. and 10:30 a.m. for those items.

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