Creamy fish pie

1 Preheat oven to 180°C. In a large saucepan, place potatoes and cover with enough cold water to allow for cauliflower to be added later. Bring to the boil over a high heat. Reduce heat and simmer for about 20 minutes until tender. About 5 minutes into simmering time add cauliflower. When the potatoes and cauliflower are soft and cooked through, drain well and mash with ½ cup of the milk and 1 tablespoon of the spread. Season with black pepper.

2 Meanwhile, heat a large frying pan or saucepan over medium and place remaining spread and leek in it. Cook for 5 minutes, stirring. Add flour and stir well for 1-2 minutes. Gradually stir in remaining milk, taking care to avoid lumps and sticking. Cook, stirring, for a further 3-4 minutes until thickened.

3 Remove from heat and stir in mustard, fish and vegetables. Season with a pinch of salt and pepper. Pour into a large ovenproof dish, then spoon over potato and sprinkle with the grated cheese.

4 Cook in the oven for 15-20 minutes until golden and bubbling at the edges. Garnish with parsley, if using.