Celeriac Soup with Hazelnut & Sage Pesto
This is my favourite soup to make during the winter months. The flavour of the celeriac is celery-like with nutty undertones, and the consistency of the soup is so creamy. The pesto also adds delicious crunchy texture and earthy flavour. You can make it a few days ahead as it freezes really well, so double the recipe when you are making it so you have a batch for a rainy day! I sometimes add a crumble of crispy, smoky pancetta on top with the pesto. 50g butter 1 celeriac, peeled and chopped 1 celery stick, chopped 1 onion, chopped 75g blanched hazelnuts 1 litre hot vegetable stock 100ml crème fraîche sea salt and freshly ground black pepper FOR THE HAZELNUT & SAGE PESTO 75g blanched hazelnuts 2 tablespoons finely chopped sage 2 tablespoons extra virgin olive oil ÷Place a heavy-based saucepan over a medium heat and add the butter. Once the butter has melted, add the celeriac, celery, onion and whole hazelnuts, and season with salt and pepper. Stir well, then reduce the heat to low, cover the pan with foil or your butter wrapper and pop the lid on. Leave the vegetables to sweat for 15 minutes.
Next make the hazelnut and sage pesto. Place a frying pan over a high heat, add the hazelnuts and toast, shaking the pan frequently to toast the nuts evenly, for 3 minutes – this will release all the oils and the flavour. Add the chopped sage to the extra virgin olive oil in a small bowl. Tip the toasted hazelnuts onto one half of a clean tea-towel, then fold over the other half of the tea-towel to cover and bash the nuts with a rolling pin until crushed. Add the crushed nuts to the olive oil and sage, mix together well and set aside.
Add the hot stock to the vegetables and bring to the boil, then leave to cook, uncovered, for about 15 minutes until the vegetables are tender. Transfer the soup to a blender or food-processor, or use a hand blender, and blend to a smooth consistency.
Return the soup to the saucepan (if necessary). Stir in the crème fraîche and place over a medium heat for just 2 minutes to warm through. Serve the soup in warmed bowls with the hazelnut and sage pesto drizzled on top.