Heat the olive oil in a large saucepan over a medium heat and sweat the onion and garlic together with a little salt for 4-5 minutes until they start to soften. Stir in the cook chopped beetroots and cook for a further 2 minutes.
Cover with the stock and bring to a simmer. Remove from the heat and stir in the cream.
Purée using a stick blender until smooth and adjust the seasoning. Ladle into serving bowls and garnish with the finely diced beetroot and a sprig of rosemary.
Freezing and defrosting guidelines
Make the soup, then leave to cool at room temperature. Freeze (without garnishes or toppings) in a rigid container, leaving a bit of space for expansion, for up to 1-3 months. Reheat either from frozen or defrost in the fridge overnight. Once piping hot, add toppings or garnishes and serve.