Sweet Potato & Pecan Cookies

Preheat the oven to 180°C (160°C Fan)/350°F/Gas 4.

Place the sweet potatoes on a roasting tray, pierce the skin with a fork and roast for 40 minutes until soft. Remove from the oven and leave to cool.

Alternatively, peel and dice the potatoes, pop in a heatproof bowl in the microwave and cook on high until soft. Blitz in a food processor until smooth.

Beat the butter and sugar in a bowl until light and fluffy, then beat in the egg and vanilla seeds (an electric hand whisk is useful here).

Then add the flour, 100g of the sweet potato purée, the pecans and hazelnuts and fold in using a large metal spoon.

Lay a sheet of clingfilm on a work surface. Scrape the cookie dough onto the clingfilm, then roll into a sausage. Place in the fridge for 30 minutes to chill.

Preheat the oven to 180°C (160°C Fan)/350°F/gas 4. Line a large or 2 medium baking trays with baking parchment.

Cut the cookie dough sausage into 8 equal slices. Place spaced out on the tray(s) and bake for 8-10 minutes. If using the marshmallows, place one in the centre of each cookie halfway through baking.