BOISE, Idaho—When the economy nose-dived several years ago, Lou Aaron found it impossible to get a bank loan, forcing him to use six different credit cards to keep his 1950s-style drive-in restaurant running.

Now, the 50-year-old chef said banks are coming to him offering loans. His sales are climbing, and he expects to borrow $350,000 to open a third location next year where he will sell prime rib, hamburgers and his "Idaho Ice Cream Potato" dessert.

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