The Walnut

9 Croall Pl, Edinburgh

0131 281 1236

Lunch/Dinner: £18-£24

Food rating: 8½/10

I MADE a number of unsuccessful attempts to book a table at the Walnut, but it was always full. The nearest I got to eating there was walking by outside. It doesn’t look that remarkable, hunkering down by a noisy arterial route, more of a modest cafe than a restaurant, or so it could appear. Its smallness helps explain why it's so over-subscribed – no more than 20 covers, I’d guess. But this in itself doesn’t account for its popularity so by the point I eventually get a booking for 4pm in the afternoon – lunch and dinner are yet again booked out – I’m curious to see what the fuss is all about.

The prevailing wisdom of modern restaurant criticism has it that in the absence of an Escoffier-style kitchen brigade, menus are generally better short and sweet, that now familiar line-up of three or four options each for starters and main courses. But the Walnut offers more dishes than it has chairs. These options are chalked up on the blackboard; its snowy smudges suggest that the line-up changes often. And while I generally subscribe to the view that a compact, well thought-out menu tends to produce better results than longer ones, I’m relishing the choice today because so many of the options actively appeal.

There are two soups (fish or pea and ham) and three salads: roasted carrots, goat’s cheese, walnuts, sherry vinegar; salmon, mussels, beetroot and horseradish; heritage tomatoes in an Italian Caprese-style line-up. And that’s before you consider the scallops, the mussels with chilli, bay, and lemon, or the chicken liver parfait with pickled cabbage and homemade oatcakes. That the oatcakes are made on the premises shows a laudable commitment to observing the "all home-made" principle, which seems hard-wired at the Walnut. Bread too is baked in the kitchen – big, sprawling, loose-knit, ciabatta with an airy, bubbled consistency and a chewy, black, sea-salted crust. Main courses tout several fish (skate, hake, salmon) and shellfish options. Duck confit is given a cassoulet treatment with borlotti beans. There are no fewer than three creditable vegetarian options.

Unpretentious normalcy characterises the front of house and the clientele at the Walnut: no city centre posing here. Yet the food is pleasingly precise. Ham hock has the tessellated mosaic effect of terrazzo flooring. Pink, moist, and suitably jellied, it comes with two halves of soft-boiled egg, curls of fennel, watercress fronds and a lively salsa verde of emerald parsley and dainty capers. Fish soup has the colour of a newly fired brick. This isn’t a classic Mediterranean fish soup in that it's thinner, and its residual iodine tang stands in for full-on fishiness, but its refreshing orange peel, chilli and hint of saffron charm stimulates the appetite; a lick of aioli and curls of parsley oil round it out further.

And here’s the hake: two chunky squares, their skin first fried crisp, then topped with an inky black olive tapenade. Below the hake sits first a brandade-style mash of smoky haddock and parsley under a salad of very thinly-sliced yellow and red "heritage" tomatoes (that for once actually taste of something), spiked with fresh mint, and just a few ultra-fine slices of mellow, pink Breton onions. A long, thick slice of honey-cured pork belly moistened by punchy wholegrain mustard gravy yields succulent, soft strands of meat and brittle crackling. Bubble and squeak could do with more cabbage, soft, French-style black pudding adds to the heft, and I’m not sure that even strikingly glazed as it is, I really want parsnip in June. That said, summer is a theoretical season in Scotland, so a wintry dish always has its place.

A long, thin baton of gooey brownie drizzled in caramel sauce, with cream on the side, is too close to an uncooked cake mix for me. I much prefer the simple Bakewell tart with its restrained jam layer, squidgy frangipane that tastes of creamy fresh almonds, not almond essence, and its sandy shortcrust pastry.

Like the titular tree fruit, the Walnut is small, and if not perfectly formed, wholesomely and honestly close to it.