Peel the chestnuts. We'll cook them without their shells so they hold their shape well. When you peel raw chestnuts, the shells are a little harder than when you cook them in their shells first. But the chestnuts themselves are also a little firmer, so the thin skins come off a little more easily and the chestnuts stay whole. Cut off the tip and slit the shell downward with a knife.

You can also cook them first and peel them afterward. In that case, I usually use a separate saucepan. Peel them once they have cooled a little but are still warm. The chestnuts may crumble a little as you peel them, though.

Peel the sweet potato and cut it into pieces. Cook the chestnuts and sweet potatoes together in plenty of water for 17 minutes (it doesn't have to be exact, just a little over a quarter of an hour). Then drain. Using pumpkin? It needs a slightly shorter cooking time, a little under a quarter of an hour. It's best to cook it separately.

Toward the end of the cooking time for the sweet potatoes and chestnuts, chop the onion and sauté it in a little mild olive oil. Add the herbs and spices and sauté briefly.

Once the chestnuts are cooked, cut them in half. When the onion starts to brown a little, add the halved chestnuts. Sauté everything briefly.

Finally, add the kale and sauté. Just a few minutes is enough. It can stay slightly crisp.

Mash the sweet potatoes. Add a drizzle of extra virgin olive oil and a little salt. Serve with the kale and chestnuts on top.