How to make roasted butternut squash soup with crispy cavolo nero

The shorter days call for warming soups that make the most of the season’s produce, says Julia Platt Leonard

Crispy cavolo nero adds a welcome crunch (Photography by Julia Platt Leonard)

Roasting vegetables brings out a sweetness and complexity that boiling can’t.

Cooked at high heat, butternut squash caramelises, tasting both nutty and savoury – the perfect base for a vegan autumnal soup.

The key is to choose a roasting pan that is big enough to handle all your veg in one layer.