Celeriac, sprouts and bacon soup recipe

Ingredients

• 30 g butter
• 2 tbsp sunflower, rapeseed or olive oil
• 1 medium onion, chopped
• 500 g celeriac, peeled and cubed
• 700 ml vegetable stock
• 200 g Brussels sprouts, trimmed and sliced
• 6 rashers of unsmoked streaky bacon or pancetta, cut into small lardons
• 100 ml double cream, or milk (if you prefer a lighter soup)
• 1 pinch sea salt and freshly ground black pepper