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Gluten Free Roasted Red Onion Soup with Polenta Croutons

Serves 4


  • 800g red onions, peeled and quartered
  • tbsp olive oil
  • 15g dairy-free margarine
  • salt and pepper
  • 250ml dry white wine
  • 1.2 litres vegetable stock
  • fresh rosemary sprig, plus extra to garnish
  • tsp chopped fresh thyme
  • tsp Dijon mustard

For the croutons

  • 300 ml water
  • 60g fine instant polenta
  • 1/2 tsp salt
  • 1 tbsp chopped fresh rosemary
  • olive oil, for brushing


1. Preheat the oven to 200°C/400°F/Gas Mark 6. Put the onions and oil into a roasting tin and toss well. Dot with the margarine, season to taste with salt and roast in the preheated oven for 45 minutes, turning occasionally, until very tender and slightly blackened around the edges. Remove from the oven and leave to cool slightly,

2. Discard the outer layer of each onion segment if crisp, then cut the remainder into thick slices. Put the onions into a large, heavy-based saucepan with the wine and bring to the boil. Cook until most of the wine has evaporated and the smell of alcohol has disappeared.

3. Stir in the stock and herbs and cook over a medium-low heat for 30-35 minutes, or until reduced and thickened. Stir in the mustard and season to taste with salt and pepper.

4. Meanwhile, to make the polenta croutons, heat the water to boiling point in a saucepan. Pour in the polenta in a steady stream and cook, stirring constantly with a wooden spoon, for 5 minutes, or until thickened and the mixture starts to come away from the sides of the saucepan. Stir in the salt and rosemary.

5. Cover a chopping board with a sheet of clingfilm, then, using a palette knife, spread out the polenta in an even layer about 1cm 1/2 inch thick. Leave to cool and firm up. Cut into bite-sized cubes, brush with oil and arrange on a baking sheet. Cook in the oven, turning occasionally, for 10 – 15 minutes, or until crisp and lightly golden brown.

6. Remove and discard the rosemary from the soup. Transfer half the soup to a food
processor or blender and process until smooth, then return to the saucepan and stir well. To serve, ladle into 4 warmed bowls and top with the polenta croutons and sprigs of rosemary.

Nutritional Fact

Onions contain sulphur which is a very important component of all body tissues, and may help to heal the gut, as well as protect against cancer,

Serving Analysis

  • Calories 218
  • Protein 3.2g
  • Carbohydrate 22.5g
  • Sugars 8.7g
  • Fat 8.7g
  • Saturates 0.6g