1: Preheat the oven to 200°C/Fan 180°C/Gas 6. Line a baking tray with baking parchment. Using a food processor, pulse the onion, carrot and celery until finely chopped.

2: Lay the slices of sourdough on the lined baking tray and drizzle with half the olive oil. Place a mushroom, cup side up, on each slice of sourdough.

3: Heat the remaining olive oil in a large non-stick sauté pan over a medium heat. Add the onion, carrot, celery and garlic and cook for 10–15 minutes or until softened and starting to caramelise. Add the lentils, vegetable stock and thyme leaves and cook for 5 minutes, or until the liquid is reduced by half. Remove from the heat and season with salt and pepper to taste.

4: Spoon the lentil mix into the mushroom cavities, piling it up high. Bake in the oven for 20 minutes, then remove and turn on the grill.

5: Crumble the blue cheese on top of the filled mushrooms and place under the grill for 5 minutes, or until the cheese has melted.

6: Meanwhile, in a bowl, dress the salad leaves with a little lemon juice, extra-virgin olive oil, salt and pepper. Serve the mushrooms straight away, with the leafy salad on the side.