Peel and cut the sweet potatoes into cubes. Place them in a large pan of boiling water and cook for about 10-15 minutes or until soft. Drain and return to the pan. Mash until smooth and creamy (add a splash of plant-based milk or vegan butter if desired). Season with salt, pepper and nutmeg. Set aside.
Preheat the oven to 200°C.
Finely chop the leek and garlic. Peel and dice the carrots.
In a large skillet or frying pan, heat the rapeseed oil over medium heat. Add the leek, garlic and carrots. Sauté for 5 minutes until softened slightly.
Stir in the vegan mince and cook for about 5 minutes.
Add the rosemary, bay leaves, thyme and tomato paste. Fry for another 2 minutes.
Sprinkle the flour and smoked paprika over the mixture. Stir well. Deglaze with soy sauce and vegetable stock, stirring until thickened.
Add the peas and chopped parsley. Cook for 2-3 minutes until the peas are heated through.
Transfer the filling to a baking dish and spread evenly. Top with the sweet potato mash, smoothing to cover.
Bake for 20 minutes, until golden brown on top and bubbling underneath. Leave to rest for 5 minutes before serving.