Heat the garlic oil in a large saucepan, then soften the onions for 5 minutes. Add the cumin and chilli, cook for 2 minutes, then add the sweet potatoes, lentils and stock,
Bring to a boil, then simmer for 5 minutes until the lentils are tender. Blend until smooth or mash and leave chunky.
Season, then transfer to one freezer-proof container, or portion into separate containers if you only want to eat one portion at a time. Cool completely and freezer for up to 3 months.
Meanwhile, unroll the pastry with the longer side closest to you, then spread the mango chutney. Scatter the cheese on the right half of the pastry, then fold the other side over it.
Press down a little, then cut into 8 strips starting from the folder edge. Twist the strips, then freeze on a baking sheet. Once solid, pack into a freezer-proof container.
Preheat the oven to 220 degrees Celsius, gas mark 7.
To reheat the soup, place it, frozen, in a large, deep frying pan with 50ml water, cover and cook over a low heat for 25-30 minutes, stirring occasionally until piping hot, adding a little water to loosen if needed.
Meanwhile, bake the frozen twists on a parchment-lined baking sheet for 15-18 minutes or until puffed and golden. Finish the soup with a drizzle more garlic oil and a few chilli flakes to serve.