Fill your kettle and boil it. Peel the onion and finely chop it. Place a medium-sized pan on a medium heat and add ½ tbsp oil and the onion to the pan. Season with a pinch of salt and pepper. Fry, stirring often, for 4 mins till the onion starts to soften and brown.

While the onion fries, peel the sweet potatoes and chop them into bite-sized chunks. Stir the sweet potatoes into the onion with 1 tbsp mild curry powder and a pinch of cayenne pepper (it's very spicy, so use as much or as little as you prefer. You can add more cayenne at the end if you like). Fry, stirring, for 1 min.

Tip the buckwheat into the pan. Pour in the coconut milk, then top up the pan with 200ml boiling water. Stir to mix, then pop a lid on the pan (or use a baking tray) and bring to the boil. Turn the heat down a little and simmer for 10 mins.

While the buckwheat simmers, pull the soft leaves off the kale cores. Finely shred the leaves.

Stir the kale leaves into the pan and simmer, without the lid on the pan, for 3 mins till the kale and buckwheat are tender.

Taste the one-pot and add a pinch more salt if you think it needs it. Ladle the stew into a couple of warm bowls and serve.