These have a sweet and slightly nutty flavour, a pretty orange colour and a wonderfully soft texture.
- Preheat the oven to 220 C (425 F/Gas 7).
- Cut the sweet potato in half and place on a baking sheet, cut side down.
- Roast on the centre shelf for about 30 minutes, or until tender.
- While the sweet potato cooks, make the pesto. Toast the hazelnuts in a dry frying pan over a medium-low heat until golden and the skins have split.
- Rub between a rough tea towel to help get the peel off.
- Place in a food processor together with the rest of the ingredients.
- Run at high speed until the desired consistency is reached, adding a splash of water if needed.
- When the sweet potato is cooked, leave until it is cool enough to handle then scoop out the flesh and mash it with a fork in a wide bowl.
- Stir in the egg, salt and nutmeg and mix until combined.
- Sift together the flours and add two-thirds to the sweet potato.
- Stir together quickly until combined.
- Dust a work surface with some of the remaining flour and turn the dough onto it. Knead the dough very gently with your hands, adding more flour if needed.
- The dough should be moist but not sticky. Divide the dough into four portions.
- Dust with more flour and roll one portion into a long log, 1 cm wide.
- Use a knife or metal pastry scraper to cut the log into 2.5 cm pillows.
- To shape the gnocchi, dust a fork with flour, place a piece of gnocchi with the cut side towards the back of the fork, press lightly with the fork and roll it down to create the tiny ridges.
- Alternatively, simply press the fork into each gnocchi – they will be more square, but will still taste good.
- Repeat with the remaining portions.
- Bring a large saucepan of salted water to the boil over a medium – high heat.
- Carefully drop in about 15 gnocchi. When they float up to the surface (after about a minute), wait 30 seconds and then fish them out of the water with a slotted spoon.
- Keep warm while cooking the remaining batches of gnocchi.
- Serve them warm with a few spoonfuls of Kale & Hazelnut Pesto (or whatever you prefer) and a drizzle of olive oil.
- You can also save the gnocchi for later and give them a quick fry in a buttered skillet together with vegetables or any kind of sauce.
Extract taken from Green Kitchen Stories by David Frenkiel and Luise Vindahl.
Photography by David Frenkiel.