LOUISVILLE, Ky. (WDRB) -- Each year, around Kentucky Derby time, a sweet sensation takes over Louisville.

The sensation involves a signature dessert -- Derby Pie.

The signature dessert of the first Saturday in May is all about a hands on approach -- and starts at the top with Kern's Kitchen Owner, Alan Rupp. "I'm glad to get out there on the line and help pack or whatever needs to be done," Rupp said.

Rupp inherited Kern's Kitchen and the Derby Pie tradition from his grandparents who started the business from scratch back in the 1950s.

"They were operating out of a 15-by-15 foot production facility," Rupp said. "We were baking six pies at a time and today we're baking a few more. We're baking 80 at a time."

Production really fires up during the two months leading up to Derby with the factory cooking up more than a thousand pies a day. Behind all that goodness is just eight people on the line.

"You don't see anybody back there just pushing a button and a pie spitting out the other end. It's all hands on and quality and taking a look at a small batch," Rupp said.

Hand sorted nuts and hand-mixed dough that's placed into the over by hand. That personal touch is what Rupp says sets this signature dessert apart from the competition. "We started with such small beginnings and we're still putting out a wow product," he said.

This marks just the second year in their new facility, where Derby Pie starts with the flaky crust, just like Grandma used to make -- kind of.

"You saw the dough mixer back there. It's a little bit larger than her taking a fork and a knife and cutting that shortening into the flour. We're doing about 180 pounds at a time," Rupp said.

From there, each pie is pressed, hand-trimmed and then filled with the secret recipe.

"I'd love to draw back the curtain for you when it comes to the recipe, but that's where all the secret stuff happens. It's kind of a "Wizard of Oz" moment. Pay no attention to the man behind the curtain."

Instead, a tube carrying the filling is the closest most people get to the secret Kern's family recipe.

Only two people outside the family have been let in on the key ingredients and Rupp says it's going to stay that way. "Well it's a secret recipe. If it's going to be a secret recipe, then it's got to be a secret," he said.

It's just one more thing that makes Derby Pie, the big race and this time of year so special.

"You've got all those things going on on your plate. It's a celebration. I think that's how it works in with Derby real well," Rupp said.

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