When it comes to oysters, you have to start with one question: who ever thought of eating an oyster in the first place? I like to think it all began with a hungry caveman who took the chance - and became the world's first gourmet.
Modern refrigeration and transportation have made it possible to indulge an oyster appetite anywhere and anytime. But for my money, there's no better time and place than an autumn day in the City-by-the-Bay.
In San Francisco, they're serious about seafood - especially oysters. So to start, I make a pit stop at the Swan Oyster Depot.
Steve Sancimino and his family run this 95-year-old shrine to seafood. They make a knockout shrimp-and-crab salad with Louie dressing, but raw oysters are the star attraction - for many reasons.
For one, said Sancimino, people believe oysters have an aphrodisiac quality.
"Well, is that something that you believe in?" Flay asked.
"As far as selling an oyster: if you're buying it for that reason, I'm selling it for that reason," he replied.
The verdict is still out on whether oysters really are Viagra-on-the-half-shell. But it's a fact that their flavor depends on one thing above all else: the water in which they're grown.
"The western oysters, predominantly, have more flavor, more unique character, because of the different growing areas," Sancimino said. "Plankton, kelp is what thrives in this area, and that's what these oysters filter on.
"East coast: more sandy, clearer water, so you get a more salty taste."
Simply put: oysters, like all seafood, depend on healthy, clean water. And the oil now polluting San Francisco Bay after a recent shipping accident has brought that message home with a vengeance.
Fortunately, most commercial oyster beds were spared. Many are about 50 miles north of the city, in Tomales Bay, where the water's pristine - and the views aren't bad, either!
Take it from me, there are few better ways to start your day than by hitting the water with marine biologist-turned-oyster farmer Terry Sawyer of the Hog Island Oyster Company.
Terry and his crew hand-raise their product - anywhere from a year to three years to get them ready for the plate.
"Oysters like to grow on each other or cluster up," Sawyer said. "That's where in the wild you have oyster beds."
"You keep them separate?" Flay asked.
"If they do attach, we'll try to break 'em apart. So it's like, 'This is the way you're going to live, as a single!'"
Many believe oyster farming is one of the most environmentally sensitive ways to produce food from the sea. As for taste, there's nothing better - or safer.
And while going raw has its pleasures, it's only half the story: apply some heat, and the oyster reveals an entirely different side.
Barbecuing oysters is one way to help those who are perhaps a little squeamish about eating their oysters raw.
Alex Klarkowski is head chef at Nick's Cove on Tomales Bay. All he needs is a dab of butter, a splash of sauce and a hot grill. The oysters do the rest.
He poaches them lightly in their own juices, cooking them medium rare. "Just until they bubble," Klarkowski said.
Even after a bath in the deep fryer, the oysters at Nick's stay plump and juicy.
It's a far cry from the kind of dish a caveman might have enjoyed. But you know what? Something tells me he'd approve.