Behind-the-scenes look at Philz on National Coffee Day

SAN FRANCISCO (KGO) -- September 29 is National Coffee Day and this morning you might've celebrated the holiday without even knowing it.

Holiday or not, the line is always long at Philz Coffee in San Francisco.

Philz Coffee was started by Phil Jaber. "You know coffee's an art, like Frank Sinatra was born to sing. I was born to make coffee," Jaber said.

He and his son grew the business one cup at a time, and one store at a time. "We're building culture at Philz. We're not just building coffee shops," Philz Coffee CEO Jacob Jaber said.

The size of the new roasting facility should tell you something. "It holds up to 15,000 pounds of green coffee," one woman said.

Philz has big plans to grow. They just announced a third round of venture capital at $45 million. "We're in L.A. now, we've opened in Washington, D.C. and Boston will be our next market," Jacob said.

And that means getting more beans from all over the world and roasting them just right. The roast is an art, controlled by computer. "When it's rising, when it's dropping, how long they want it to linger at a certain temperature," Philz Director of Coffee Andi Trindle Mersch said.

There could be a blend of seven types of coffee in one cup of Philz Coffee. "My dad and I are the only ones who know what's exactly inside of the blends," Jaber said.

In the end it all comes down to flavor and that's decided by a panel of expert tasters in the cupping lab. Strict procedures keep the recipes secret. So, even the people roasting the beans don't know what blend they'll end up in.

But for Jacob, the most important ingredient is people. "Finding the right people, inspiring them, investing in them," he said.

And training them at Philz University where National Coffee Day is, every day.