Nan Kohler is the founder-proprietor of L.A.’s sole artisanal stone mill. Grist & Toll is located in a small industrial complex at the south end of Pasadena’s Arroyo Parkway.

Nan grew up in Missouri. She’s been an avid home baker her whole life. She was in the wine industry for six years. She’s used to thinking about agriculture and terroir and growing seasons.

“We know our peaches, we know our heirloom tomatoes, but we’re still missing that connection with wheat. We need to develop a palate for wheat, the way we have for coffee and wine. Different types of wheat have different flavors, baking characteristics and aromas. And nobody’s been talking about it for a long, long, time.”

Almost every city grew up around a mill. The first commercial building in L.A. was Capitol Milling. The oldest building in all of Southern California is El Molino Viejo. “Farming, wheat, baking and bread were part of daily life. The mill was a natural epicenter for newsgathering, information-sharing and fellowship.”

At the front counter of her own store, Nan shows me three stalks of wheat: rye Sonora, a heritage soft white wheat and a hard red wheat.

“Those stiff little bristles growing from the ear are called awns. First, you have to remove the chaff, the papery hull. In really old times that was a very physical thing, done by hand and with the wind.”

“Grist” is the raw product: the cleaned berries the farmer toted to the mill. As partial compensation for turning the grist into flour, the miller was allowed to take a “toll”: a percentage of what he milled, either to sell in his shop or to feed his family.

Nan’s own wooden mill was made to order by a family-owned company in Austria. She demonstrates the loader that can handle up to a ton of grain at a time, the stainless steel auger, the motor that moves the grain and drops it into the milling machine. The grain is then ground between two 42-inch stones.

“Whole grain flour, properly milled, can be more, not less delicate, than the flour to which we’re accustomed. Good flour is like baker’s crack. You make a simple shortbread cookie with one of my flours, and suddenly there’s richness and depth and personality and life.”

It would be nice if a product like Nan’s could slide right into the marketplace at an easy, competitive price point, but nothing about the process is going to make that doable for a while.

“There’s no handbook for a place this size. How do you put together an air-cleaning system? How do you develop a relationship with the California Wheat Commission up in Sacramento? What does it mean to have a farmer save seeds for us and to plant each season?

“But people walk through that door and I know it’s absolutely worth it. My customers say, ‘Thank you for doing this.’ There’s a hunger.”

What’s her take on the gluten-is-poison idea?

“That’s a five-hour conversation. Is gluten bad? No. Are there some people to whom it’s life threatening? Of course.

“But our culture has a history of wanting a simple solution and one really bad thing to point our fingers at instead of taking a hard look at some of our choices.”

“An over-processed, damaged, basically dead product is artificially reassembled into white bread in four hours or less. Then it’s super-glutened to withstand the aggressive mixing. Everything has to be bigger and faster.

“So we need to rethink our relationship to the cost of bread. We pay $4-6 for a cup of good coffee. A real loaf of bread with fresh hand-milled flour and two hands that shaped and proofed and baked it, over a period of three days? I think that’s worth more than our cup of coffee.”

The learning curve has been steep. The struggles are ongoing.

“People want scones and muffins and bread made with this flour. We can’t do it. We’re millers, not a commercial kitchen. But the home bakers are tearing it up. They are fearless. They are excited. They’re experimenting.

“More and more professional bakers and commercial kitchens are coming to us. But I believe the home bakers are the ones who will actually drive a bigger spread, a bigger interest.”

The whole spectrum of life in L.A. shows up at her door: crunchy granola, hipster WeHo, little old ladies, tattoos.

“And you wouldn’t believe the number of men in Los Angeles making sourdough bread, pizza and pasta from scratch! Hanging out here on a community bake day restores your faith in humanity.”

As we talk, an older woman comes in to stock up on farro flour. A skateboarder picks up a bag of black barley.

Out back, Nan removes the lid from a bin of rye flour.

“You saw those raw berries. Wait till you smell that aroma, malty, rich.”  The color is a pale celadon green. I breathe deeply: heaven.

“To look at your flour,” Nan winds up, “is an invitation to look at your neighborhood, your earth, your body, your soul.”