With numbers dwindling, sightings have been increasingly rare, but researchers confirmed today that a neighbourhood restaurant has settled in the Gladesville-Hunters Hill region.

"We haven't seen one of these for a while," said a spokesperson for the mythical not-for-profit association, Save Our Suburban Restaurants. "So it really did the heart good to know they're still out there."

Local, family-run restaurants have been in decline for 30 years or more, as suburbs have been ravaged by feral fast food chains. But Boronia Kitchen shines like a beacon on its dark section of Pittwater Road.

Chef Simon Sandall and co-owner Susan Sullivan both worked with Matt Moran and Peter Sullivan in key long-term roles for the MorSul restaurant group (now Solotel), which included Chiswick and Aria. Sandall is one of those chefs who can feed 200 as well as he can feed two; and Sullivan wrote the book on hospitality and staff training. They're practically endangered species themselves.

Now they've gone casual, local and low-key with a something-for-everyone, all-day diner fed by its own kitchen garden. The double shopfront doors open to a gleaming open kitchen, revolving rotisserie grill, piles of quinces and pumpkins, loaves of bread; and a busy kitchen and floor team.

It's a move that has made it an immediate magnet for breakfasts of avocado and feta on toast and bacon and egg rolls; lunches of prawn spaghetti and lamb and quinoa salad; and takeaways of soup and house-made sausage rolls.

At night, things get a little more glamorous, from house-smoked salmon to battered King George whiting and chips, and whole roast chickens from the rotisserie. But I've fallen for the prawn toast ($19), a single slab of sourdough encasing a sweet and light prawn mousse, it's crusted with black and white sesame seeds, deep-fried and dotted with yuzu mayonnaise. Genius.

Cured wagyu ($23) is sliced and served with onion curd, cress and house-made king edward potato crisps, and is nice enough.

At this point I look around and think to myself "this must be the happiest restaurant in Sydney". Early bookings are after-school families, the parents engaging with the kids, doing taste tests on chicken and green vegetables, critiquing coloured crayon drawings. It's a scene from an earlier, more Rockwellian time, before iPads and babysitters were invented.

Later, it's couples and foursomes slipping into booths, their comfort-food buttons pressed by '90s-style confit duck ($32), with a crusty duck meat croquette and almond puree, surrounded by peas and mint leaves.

At last it's rotisserie time. A hunk of blistery-skinned,spit-roasted pork belly ($28) comes with a coral-like outcrop of snow fungus, a wodge of cavolo nero, and a pool of some of the smoothest, snowiest mash I've hoovered up in a long while. Equally silky is a Sinapius Esme Rouge gamay ($80) from Pipers River in Tasmania, from a smart wine list marked with indicators for minimal intervention and biodynamic wines.

Dessert-wise, it's hard to go past the tarts – either the sticky goo of treacle ($16) or a classy wedge of chocolate and strawberry ($16).

How good to see a bustling suburban restaurant that's not only alive and well, but is overdelivering on top produce, high detail and hospitality. I'm with the SOSR – support your suburban restaurant today, while you still have one.

The low-down

Boronia Kitchen

Drinks: Single O coffee, smoothies and spritzes, and a lively, useable, naturalist wine list from Luke Sullivan

Vegetarian: two dedicated starters and one main

Go-to dish: Roast pork belly, cavolo nero, mushrooms, potato puree $28

Pro tip: Repeat after me: I will order anything from the rotisserie

Terry Durack is chief restaurant critic for The Sydney Morning Herald and senior reviewer for the Good Food Guide. This rating is based on the Good Food Guide scoring system.