The ENQUIRER exclusively reports  Nicole Kidman meltdown!

Preggers Nicole exploded when down-home hubby Keith Urban took her to the Cracker Barrel in Crossville, Tennessee for lunch.

"The food seemed to be fine for him because his wife didn’t even bother to look at the menu," said an eyewitness. 

"She’s more accustomed to haute cuisine but Keith’s tastes are simpler."

But when Nicole got a load of the southern-style chow, she hissed, "’This is it?  This is where we’re getting lunch – I hate this place! Everyone is staring at us…’."

According to witnesses, an uneasy Keith whispered to Nicole to calm down.

She didn’t.

Nicole stormed out of the restaurant with a sheepish Keith following. 

They then battled in the parking lot.

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