Sit down at Chez Panisse and dinner starts, just like that. No scripted introduction, no mission statement, no spiel. Not even a little, “Have you dined with us before?”

If you didn’t already know that Alice Waters opened this place 55 years ago in Berkeley, Calif., that it became one of the most important restaurants in the country, mothering the modern farm-to-table movement and an era of rustic, ingredient-obsessed American cooking that leaned heavily on France, well, you could wrap up dinner and polish off your pluot galette without anyone tipping you off

You might expect Chez Panisse to hammer home the values of building education and community through fresh local food that Ms. Waters has been promoting for decades, that it would pause now and then to flex. But dinner here is never didactic. It flows in the quiet, straightforward way of a bistro that’s been around forever. Service is calm, self-possessed, attentive, sometimes a little detached in the way that makes Americans complain about Parisian restaurants.

Chez Panisse is still devoted to pristine seasonal ingredients from small farms and to preparing them like a romantic home cook from another century. Its aesthetic was imitated until it became an inescapable cliché, but was also pushed forward by more expressive and experimental kitchens.

As a result, a meal here can now feel both wonderfully timeless and oddly stuck in time, so much so that it came as a surprise when Bar Panisse opened in December — a new act, directly next door. How would a modern restaurant interpret the culinary ethos that, half a century ago, transformed American food culture?

Chez Panisse opened in 1971, rebelling against both mainstream industrial food and healthy-ish hippie counterculture.

It’s now divided in two, the restaurant downstairs run by the chefs Amy Dencler and Martin Fabre, and the cafe upstairs run by the chefs Nathan Alderson and Ann Cromley. Downstairs, there’s a set menu that isn’t a tasting, but a pleasant, sensible, unfashionably tight four courses. (Add a cheese course if you like.)

Recently, I had an excellent dish of pork, roasted on a spit then sliced very thinly, with cherries and fried herbs, with a splash of pan sauce. I did worry at first glance about a salad that resembled a fairy crown, weighed down with mounds of chopped salmon — it looked both out of proportion and underdressed on the plate, but it surprised me with a woven sense of texture and bursts of acidity.

Over the course of a few meals, I also had a couple of dishes that were technically proficient but forgettable, hazy even as they arrived. Dessert, overseen both upstairs and down by the pastry chefs Carrie Lewis and Eriko Yahiro, was consistently a joy. Dishes like an oversize profiterole with a moat of summer fruit, or a medley of sorbets with a curved tuile, were a reminder of how the most banal classics can bring so much pleasure when they’re made with care and superlative ingredients.

Upstairs, where salads and beautiful, airy pizzas are always on the menu, I ordered “Lindsey’s almond torte.” It’s a simple cake, and I’ve made it more times than I can remember, following a recipe from Lindsey Shere’s classic cookbook, “Chez Panisse Desserts.”

There is a Chez way to do everything — to buy lettuces, wash lettuces, dry lettuces, dress lettuces — and this happens to be the Chez way to bake an almond cake. With a deeply golden top that had bubbled right at the center, the cake was served that day with early blueberries in thick, dark syrup and such softly whipped cream, it could barely hold its shape.

The dessert was extremely straightforward in both flavor and presentation, a little restrained, but it reinforced the lasting power of Chez Panisse, a restaurant that finds meaning by continuously looking into the past — specifically, its own.

No, this is not a recipe for thrills, but there’s something reassuring about the way everyone at Chez Panisse seems to share an unshakable house style, built as much on ephemeral ingredients as on the kitchen’s own half-century-deep archive. Maintaining it is how the restaurant has endured, even as generations of servers and cooks have come through its doors.

Amelia Telč, the chef at Bar Panisse, is not one of them. She hadn’t worked for the group before she got the job, but like so many chefs, she had studied the restaurant’s cookbooks and absorbed its reverence for ingredients.

Ms. Telč buys from the same purveyors, approaches techniques and recipes from the same point of view, though in some ways, Bar Panisse is less technically ambitious. (It’s in the name, it’s a bar!) The menu is short, easy to share, and plates tend to have few components, but this works to bring the food closer to the kind of provincial French cooking that Chez Panisse once idealized.

Service is sharp and fast-paced and the room has energy, particularly at the bar where the drinks shift with the seasons, too. Ms. Telč writes a new menu each week, and it involves small, snacky things along with a few dishes you can make into a meal. Specials come and go, like tiny fried squash blossoms, still attached to the young zucchini, with little more than a heap of finely chopped and exceptionally sweet peperonata.

A fluffy and finely calibrated green salad is usually on the menu, as are the puffy gougères you should order alongside it. But I most looked forward to the changing platters of fat, creamy-centered butter beans, served in a shallow pool of cooking broth, which might be topped with a glug of olive oil and a halved hard-boiled egg; or braised winter greens; or slabs of smoked eggplant and garlic and a few fuzzy leaves of minty nepitella.

These platters looked like what you might put on the table at home, simple to the point of being almost unremarkable, but there was beauty and confidence in that.

The Gulf shrimp on the bar menu, so small they would usually wind up flavoring the stockpots at Chez Panisse, are fantastic. Ms. Telč might fry these shrimp and serve them whole with a splotch of lemon aioli. They’re sweet, their carapaces so delicate that you can eat them shell and all.

Strawberries from Swanton Berry Farm recently appeared ripe and raw in a Pavlova layered with a properly tenderhearted meringue and devastatingly soft whipped cream, the whole thing so fragile, it seemed to be collapsing continuously into a soupy custard until the very last bite. It was a dessert that wanted to be eaten, and fast.

Much as at Chez Panisse, there is a gentle touch to the preparations: No dish will be the most intense or loudest version of itself. At its best, this gentleness can be clarifying — particularly if you’ve gotten bored with kitchens where the salt, fat, acid and heat dials are turned all the way up, all the time. But occasionally, it’s disappointing.

On one visit, my table shared a lamb pie served with a bouquet of young, particularly tender fava leaves. The pastry was beautifully browned and crisp all over, with a thick, pinched rim, and the plate projected a kind of springy abundance. But once I dug inside, the filling was surprisingly plain, a bit dry. It was a rare misstep from a kitchen that understands that simplicity requires precision.

Bar Panisse does not take reservations, and a chatty line of locals starts outside before it even opens. Standing on the sidewalk, catching the laughter and gossip, it doesn’t feel like a destination, but a neighborhood spot — the kind of self-effacing restaurant where you know you’ll be taken care of while you eat and drink well.

In its warmth and spontaneity, its scrappiness and sprightliness, Bar Panisse is somehow both attuned to the way we dine now and true to the restaurant’s original spirit. Chez Panisse might have forever changed the way we think and talk about food, but it also seems less interested in its own mythology than the ordinary, unglamorous work of being a good restaurant. That’s not revolutionary, but it’s still rare.

Tejal Rao, our chief critic based in Los Angeles, writes starred reviews of restaurants nationwide. Ligaya Mishan, our chief critic based in New York City, writes starred reviews of restaurants in New York and beyond. Briefer starred reviews of New York restaurants are written by our contributing critics Mahira Rivers and Ryan Sutton, and first appear weekly in the Where to Eat newsletter (subscribe here).