A refreshing dessert with a touch of the negroni: oranges marinated in a thyme-infused vermouth syrup.

There's a scene in The Roman Spring of Mrs Stone when Warren Beatty, playing a gigolo, is having dinner with Mrs Stone, played by Vivien Leigh. He turns to a waiter, holds up two fingers and orders, "Due negroni." I first saw this 25 years ago and had no idea what a negroni was, so I looked it up and convinced a friendly cocktail barman to make me one: ⅓ Campari, ⅓ gin, ⅓ vermouth, with a twist of orange. (A mixer-free cocktail? Hello.)

Suffice to say I ordered this drink all over town, explaining it every time and making it for my friends, who started doing the same thing. Slowly but surely, it started showing up on cocktail lists everywhere. Yes, I'm claiming some credit for driving the revival of the negroni in the 90s. Do I get a medal?

So when I saw a story recently titled "Vermouth is Back!", it was a surprise to me because I didn't know it had gone away. Besides being essential for martinis and negronis, it has earned a place in my kitchen as an ingredient, an easy substitute for any recipe that calls for a splash of white wine.

Then a friend of mine created a created a range of vermouths (this is just how I roll, people; this isn't sponsored and he doesn't know I'm writing this — hi, Wardy!) called Regal Rouge, made with Australian botanicals, so I ordered some to try it out. I'm pleased to say it's fabulous, though I do suddenly have a lot of vermouth in the house and I can't (well, more accurately, probably shouldn't) live on cocktails alone.

This dessert, one of my storecupboard standbys, is made with white vermouth – bianco, thank you – and it does have a touch of the negroni about it. Because they're so strongly flavoured, oranges need a little tough love to get them to play nicely as an ingredient, and my simple syrup of vermouth infused with thyme makes that happen.

It uses two oranges, and I use two kinds of orange, a Valencia and a blood orange, because it's pretty. You can make it from scratch to serve immediately if you like, though it is infinitely better to make it ahead and let it chill and marinate for few hours, even up to a day ahead. Cin cin!

Oranges with vermouth and thyme

For 2.

2 oranges
60ml (1/4 cup) white vermouth
60ml (1/4 cup) water
2 tablespoons sugar
1 teaspoon fresh thyme leaves (or ½ teaspoon dried thyme)
thumb-sized piece of orange rind

Peel the oranges, removing as much pith as you can. Scraping the orange with a small sharp knife – a bit like shaving it, really – is a good way to do this. Cut into thick slices and place in a bowl.

Put the vermouth, water, sugar, thyme and orange rind in a small saucepan. Stir over low heat until the sugar is dissolved.

Raise the heat until the liquid is simmering. Let it simmer away, stirring occasionally, until it has reduced by at least half. This takes about 10 or 15 minutes depending on your heat. Keep reducing until the syrup is just thick enough to coat a spoon.

Remove from the heat and let the syrup cool, then strain it.

Pour the syrup over the oranges and toss gently to combine.

Serve with a dollop of Greek yoghurt and a sprinkling of fresh thyme leaves, if using.