Moroccan fish tagine

Ingredients

• 2 tbsp olive oil, plus extra for brushing

• 2 celery sticks, chopped

• 1 carrot, chopped

• 1 small onion, chopped

• ¼ preserved lemon, finely chopped

• 4 plum tomatoes, sliced

• 600ml/1 pint fish stock

• 8 small new potatoes, cut lengthways into quarters

• 2 red mullet, ocean perch or grey mullet, weighing about 450g/1lb each, filleted

• 8 black olives, halved

• 1 tsp chopped fresh coriander

• 1 tsp chopped fresh mint

• salt and freshly ground black pepper

For the charmoula

• 2 tbsp roughly chopped fresh coriander

• 3 garlic cloves, chopped

• 1½ tsp ground cumin

• ½ red finger chilli, seeded and chopped roughly

• ½ tsp saffron strands

• 4 tbsp extra virgin olive oil

• 1 lemon, juice only

• 1½ tsp paprika

• 1 tsp salt