Nothing beats the taste of soft, richly flavoured caramelised onions. If you combine these onions with a couple of sweet potatoes, vegetable stock and seasoning, it results in a delicious, velvety soup.
- Sweet Potatoes - 450g / 1lb, peeled and roughly chopped
- Red Onions - 675g/ 1.5lb peeled and sliced
- Vegetable Stock - 1.5L / 6 cups
- Olive Oil - 2 tbsp.
- Balsamic Vinegar - 3 tbsp.
- Brown Sugar - 2 tbsp.
- Salt & Pepper - to season
Peel and roughly chop the sweet potatoes and peel and slice the red onions. Heat oil in a large frypan over low heat. Add the onions and a good pinch of salt and cook very slowly for 15-20 minutes, stirring occasionally to prevent them from burning.
When onions are softened and tinged golden, add sugar and balsamic - this will start the caramelisation process. Cook onion over low heat for a further 5-10 minutes, stirring occasionally, until sticky and caramelised.
In the meantime heat the vegetable stock in your stockpot and add the sweet potatoes. Once boiling reduce the heat and simmer for 10 minutes. Add the onions and simmer for another 5-10 minutes or until the sweet potatoes are tender.
Turn off the heat and let the soup cool down for a few minutes. Purée the ingredients with a hand blender in the stockpot or puree in batches in your blender.
Return the soup to a clean pan, and season to taste with some freshly ground sea salt and pepper.
Serve with a warm and crusty piece of bread.