Sweet potato casserole with candied rosemary pecans

1. First, prepare the pecans. Toast the pecans on a dry hot frying pan over a medium heat. They take on colour quite quickly so keep a close eye on them and move the pan regularly. They will only take a few minutes to toast. Set them aside and return the pan to a medium heat. Add the brown sugar and water. Leave to warm and simmer into a dark thick caramel. Return the pecans to the pan along with the rosemary and salt. Mix well, then tip the candied nuts on to some baking paper and leave to cool.

2. Peel the sweet potato and cut into chunks. Place in a large pan and cover with boiling water. Simmer for 15 minutes or until the sweet potato is fully cooked. Drain well.

3. Add the butter, maple syrup, cinnamon, nutmeg and season to taste with salt. Mash well till smooth using a potato masher or stick blender.

4. Butter an oven proof serving dish. Add the sweet potato purée. Arrange the marshmallows in a single layer on top, if using.

5. Preheat the grill to high and place the sweet potato dish underneath. Grill the marshmallows until they are just browning and charring in places. Roughly chop the pecans and sprinkle over the top. Serve straight away.