Cook the lentils in a saucepan of simmering water until tender, about 30 minutes, then drain well.

Pour the rapeseed oil into a frying pan over a medium heat, add the onions and fry for 10 minutes or until golden. Transfer half of the fried onions to a plate and pour most of the oil from the pan over the top.

Add the lentils to the frying pan, along with the lovage and paprika. Stir for a moment, then add the tomatoes. Bring to a simmer and cook uncovered (you want most of the moisture to evaporate) for about 15 minutes, stirring occasionally. Season generously with salt and pepper, then set the filling aside to cool completely.

For the dumpling dough, peel the potatoes, cut into chunks and place in a bowl of cold water.

Take half of the potatoes and cook them in a large saucepan of boiling salted water until soft but not falling apart. Drain well and mash until smooth.

Take the other half of the potatoes and finely grate them in a powerful food processor or on the smallest holes of a box grater so they turn to mush. Place in a bowl lined with muslin or a clean tea towel and stir through the lemon juice to stop the potato from discolouring. Now gather together the corners of the muslin or tea towel, twist them together and use your hands to squeeze out the excess water into the bowl. Reserve the soft white starch, which will settle at the bottom of the bowl, just in case you need to use a bit of it to bind the dumplings (usually this isn’t necessary, so instead I save the contents of the bowl to pour into my bathwater – it acts as a natural skin softener).

Place both grated raw and mashed potatoes in another bowl. Finely grate in the onion, then season well with salt. Using your hands, mix the potatoes and onion together. Slowly start to add a tablespoon of the cornflour with one hand while you carry on mixing with the other hand; depending on the potatoes you used, you may not need both tablespoons. The aim is to form a ball of soft dough that’s neither too wet nor too dry. If the dough feels a bit dry, add a teaspoon or so of the reserved starch.

To make the dumplings, take a chunk of the dough – about the size of a tennis ball – and flatten it so that it covers the palm of your hand. Put a good amount of filling in the middle, perhaps 2 tablespoons, then bring up the sides to form a zeppelin shape and pinch together to seal well. Repeat until all the dough and filling is used up.