It used to be a place you’d never venture on a whim.

No, the Dining Room at the Ritz-Carlton, high atop San Francisco’s blue-blood Nob Hill, was reserved for special times, when you got dressed to the nines to celebrate a planned, lofty occasion.

Those times have changed — dramatically.

The prim-and-proper Dining Room, the last of those concept restaurants at any Ritz-Carlton, finally was bid adieu late last year. In its place, the swank Parallel 37 opened, named appropriately enough for the geographic latitude running near the Bay Area.

With cocoa banquettes, bare tables and a focal point wall aglow with the image of a backlit oak forest, the new restaurant has gotten a fresh, contemporary makeover. It has a much larger bar, too, complete with two flat-screens, something unthinkable before. And parking for the restaurant has been dropped to a reasonable flat-rate of $10 to lure more folks to drop in on a regular basis.

Amid this whirlwind of change, one constant has remained, thankfully. Executive Chef Ron Siegel, who has been at the helm since 2004, is still in charge.

“I like the new look,” he says of the transformation of his restaurant. “The other was a little stuffy. People in San Francisco love to eat out and to them, this has the right feel now. I like the energy it has.”

You might remember Siegel for being the first American chef ever to beat an “Iron Chef” on the original Japanese version of that wildly popular TV show back in 1998. Many tourists still do, and make a beeline to the restaurant just because of that.

It used to be that you’d have to pay a pretty penny to dine here. Not so much any more. Gone are the lavish, hours-long tasting menus. In its place is an à la carte menu with $7 to $18 appetizers and entrees all under $30.

At the sleek soapstone bar, enjoy small bites and appetizers. Or order off Siegel’s dinner menu like so many patrons opt to do.

That’s exactly what I did when I dined as a guest recently at the bar, which is proving quite the new “It” spot in the city among the denim- and khakis-crowd after work, who congregate  at high communal bar tables.

A cocktail is a must, especially with one of San Francisco’s most talented mixologists, Camber Lay, overseeing the bar. With creamsicle bitters an ingredient, the “Missionary March” ($14) was a bright and fun blend of tequila, lime and a fresh grind of black sea salt.

Crispy chicken wings ($6) may be from the bar bites menu. But they’re like no chicken wings at any other bar. Deboned, these plump little morsels come skewered on bamboo sticks for easy eating. Lemon and Szechuan pepper added liveliness and a little kick.

Crab cakes ($8) are bite-sized morsels full of fluffy Dungeness flesh. Disks of apple and ginger gelee gave them even more “wow” appeal.

Kampachi sashimi ($15) from the dinner menu will astound. It’s so gorgeous to behold that you can’t believe you’re enjoying something so elegant and refined while propped on a bar stool. Curls of silky raw fish are arranged on a rough-hewn plate with tangy wood sorrel leaves, crisp little rice puffs, the crunch of pomegrante seeds and caviar-like finger limes. It’s a dish where time stands still with each and every lovely bite.

Siegel has a sure hand with fish, whether it’s raw or cooked. The snapper ($27)  was another artful dish. Its skin was seared crisp like a potato chip. Fragrant bamboo rice with more Dungeness crab and juicy pomelo segments added a subtle Asian flair.

For dessert, it doesn’t get better than the lemon semi-freddo ($8). A wedge of tart arrives with a rippled, torched marshmallow top drizzled with huckleberry sauce. Underneath, there’s a layer of frozen lemon custard on a graham cracker crust. It’s tangy, just a little sweet, and delightfully gooey. It’s grown-up sophisticate on the outside but all childhood fun on the inside.

The Dining Room might have been a place you ventured into once a year. Parallel 37, with its more relaxed vibe and price point, is a place that’s sure to beckon a whole lot more often.

(For more on Parallel 37 and its stellar cocktail program, see my story in Food Arts magazine.)

More: My Q&A with Chef Ron Siegel