It is not easy to support any changes to Castlemaine's grand old Midland Hotel. The historic building has been around since the 1870s and it is what you might describe as peak Castlemaine: artistic quirk and pure deco elegance, frozen in time.

Many restaurateurs have tried to capture the glamour of the 1930s, but here it is no veneer. From the ballroom to the wild guest rooms and the Maurocco Bar saloon, it's a treasure.

But new blood has arrived, and given it belongs to drinks wizard Loudon Cooper (manager of Castlemaine's equally excellent Theatre Royal), his wife Tess and chef Alexander Marano (ex The Good Table), you won't want to stand in the way of their progressive dining agenda.

The trio hasn't taken over the whole hotel; just the portion that was once a fabulous ladies' shop. Leaning on personal grit and YouTube tutorials, they've ousted the striped wallpaper to make a 17-seat, wood-panelled, white-tiled candlelit nook, perfect for the pre-lockdown winter night I was there.

As for the pitch, Bar Midland has built its menu with its carbon footprint firmly in mind.

Increasingly, chefs and restaurateurs are taking the view that how we eat is giving the planet a solid kicking, and even serving free-range proteins and a few foraged things isn't quite enough.

The menu incorporates indigenous ingredients from Indigenous-owned businesses. It celebrates heroic Victorian producers and takes a big picture view of other issues. Meat? Only if it is a wild introduced species, like rabbit or venison. Cheese? They get it from the best, which happens to be close by at Long Paddock and Holy Goat, a fromagerie quite literally helmed by a nun.

That said, dinner is far from a sermon on the mount. It is an argument elegantly made across a four-stage dinner of smaller dishes, which Marano cooks behind the main bar.

That might look like opening snacks of gougeres, savoury profiteroles piped full of a thick cheesy bechamel and showered in mountain pepper for zip. Nutty crackers made from wattleseed are crowned with quince paste and their own miniature La Luna goat's cheese, perfection the size of your pinkie. And in honour of the huge effort to revive Victoria's native angasi oyster population, they are the bivalve of choice, all mellow minerality, refreshed with finger lime.

The ambition is great here. Since refined sugar isn't produced in Victoria, they work around it, using honey or harnessing it from fruit and veg. They are even growing sugar beet to harvest sweetness of their own. Working within these tight parameters gives Marano a challenge, and he hits some major highs.

When you eat grilled blue mussels off a bay leaf spear, swinging it through a bay-infused cream that tastes like bread sauce at Christmas, it feels like the only way you should eat them. The char gives the invertebrate such a meaty, condensed backbone.

See also sweet-souled, blackened leeks with a play on ajo blanco – that Spanish sauce of blitzed almonds, bread, vinegar and oil, here made with huge native bunya nuts that grow at their own house.

Sometimes, however, execution lets down the side. Agnolotti filled with potato, ricotta and mint are a touch thick-skinned for such subtle flavours.

In principle, the ballotine of wild rabbit is everything you want to and should be eating on a wintry night. It comes with chestnuts, lemony creamed spigarello (broccoli, without the florette) and a sauce gastrique, which usually begins with caramelised sugar. But as they don't use that stuff, they have drawn it from roasted root vegetables, then deglazed the sticky caramel with house-made apple cider vinegar and rabbit stock. It's a brilliant concept, frustrated on this night by extreme saltiness in the ballotine, while our pommes Anna (razor-fine potato slices cooked with butter) are a little soft, losing the essential structure you want between the layers.

Still, the enthusiasm is infectious. Especially paired with Loudon's wine matches, which are intoxicating in every sense. You might kick off with a Manhattan full of local liquor and a native riberry garnish instead of the usual cherry. He's aligned himself with thoughtful Victorian winemakers such as Shadowfax, Lapalus and Sutton Grange, and will swing in the odd funky saison.

And while the lows give pause for a $110 menu, there are incredible highs: the spelt bread delivered daily by Marano's mum with a perfect pat of cultured butter; and the silky, almost savoury creme royale dessert – essentially a creme caramel sweetened with honey.

The rich custard, made with Schulz organic cream, smells like late summer, tastes like warm oats, and when matched with the honeysuckle-like star power of a late-harvest Scorpo pinot gris, is a home run.

Long story short, Bar Midland hasn't entirely arrived yet, but as soon as you're able to, you'll want to follow where they are going.

Cost: $110 a head, drinks match $80.

Drinks: Local heroes on all fronts: spirits, wine and beers.