Sweet potatoes with orange bitters

General

Source: Ottolenghti, Plenti more

350ml freshly squeezed orange juice (the juice of 4–5 oranges)
80g soft brown sugar
60ml red wine vinegar
60ml Angostura bitters
1½ tbsp olive oil
4–5 sweet potatoes, unpeeled, halved widthways, each half cut into 2.5cm-wide wedges (1.5kg)
2 red chillies, slit open along the centre
3 sage stems (15g)
10 thyme sprigs (10g)
2 heads of garlic, unpeeled and halved horizontally
90g chèvre (goat’s cheese) log, broken into pieces
salt and black pepper

Preheat the oven to 220ºC/200ºC Fan/Gas Mark 7.
Place the orange juice in a medium saucepan with the sugar and vinegar. Bring to the boil over a high heat, then reduce the heat to medium–high and simmer fairly rapidly for about 20 minutes, until the liquid has thickened and reduced to 200ml (about the amount in a large glass of wine). Add the bitters and olive oil, along with 1½ teaspoons of salt.
Place the potatoes in a large bowl, along with the chillies, sage, thyme and garlic, and then pour over the reduced sauce. Toss well so that everything is coated and then spread out on a baking tray that is snug-fitting but large enough for the potatoes to form a single layer, about 30cm × 40cm.
Place in the oven and roast for 50–60 minutes, turning and basting the potatoes every 15 minutes or so. They need to remain coated in the liquid in order to caramelise, so add some more orange juice if they are drying out. At the end the potatoes should be dark and sticky.
Remove from the oven and leave to cool slightly before arranging on a platter and dotting with the goat’s cheese. Serve warm or at room temperature