Beetroot and orange soup with mustard seeds | Sainsbury`s Magazine

Ingredients

• 1 bunch of raw beetroot (about 700g), trimmed, bigger ones halved
• 1 tbsp olive oil, plus extra to serve
• 50g butter
• 1 large onion, roughly chopped
• 2 cloves garlic, roughly chopped
• 2 tbsp red wine vinegar
• 600ml vegetable stock
• finely grated zest of ½ orange
• 1 tbsp mustard seeds