Step 1

Preheat oven to 400° f (200 °C)

Step 2

Peel the potatoes (or leave the peels on and wash if you prefer), then chop each potato into about 6 pieces. Put the chopped potatoes in a large pan and cover with hot water from a kettle. Add the salt, cover and bring to the boil. Simmer for about 15 minutes until the potatoes are very tender (check with a fork or knife). Drain then return to the pan and leave them alone with the lid off for a few minutes to allow them to steam dry.

Step 3

Add the milk and optional butter to the pan and mash very well until creamy. Set aside.

Step 4

While the potatoes are cooking, warm another pan over a medium heat. Add the oil (or use a little water instead to keep it oil-free) and sauté the onions, garlic and carrot until the onions are starting to go golden brown.

Step 5

Add the dried herbs, lentils and arrowroot or cornstarch. Stir well to distribute the arrowroot through the lentil mixture then add the tamari or soy sauce, followed by the tomatoes and stir well.

Step 6

Add the stock and stir again. As soon as it is just starting to bubble, turn off the heat, season with salt and pepper and spoon the lentil mixture into an ovenproof dish.

Step 7

Spoon the mashed potatoes over the top of the lentil mixture, then using a fork spread it out evenly. A few little gaps around the edges are fine. Rough the potato up with the fork (the rough bits create more crispy bits). At this point you can brush it with a little oil or vegan butter for even more crispiness, or just leave it as it is.

Step 8

Place the dish on a baking tray (to protect the bottom of your oven in case of any leaks), and bake in the oven for 30 minutes. Then pop it under the broiler/grill for a few minutes to make it extra crispy before serving.