• Boil the kettle. Half-fill a large saucepan with boiling water, then add a generous pinch of salt. Peel potato and cut into large chunks. • Cook potato in the boiling water, over high heat, until easily pierced with a fork, 12-15 minutes. Drain and return to the pan. • Add the plant-based butter and the plant-based milk to potato and season generously with salt. Mash until smooth. TIP: Save time and get more fibre by leaving the potato unpeeled.

• Meanwhile, preheat grill to high. • Slice carrot into thin half-moons. • Thinly slice celery and leek. • Thinly slice spring onion.

• In a large frying pan, heat a drizzle of olive oil over medium-high heat. • Cook carrot, leek and celery, until just tender, 3-4 minutes. • Add plant-based mince and cook, breaking up mince with a spoon, until just browned, 4-5 minutes.

• Add tomato paste, garlic paste and Nan's special seasoning and cook, until fragrant, 1 minute. • Stir in the water and vegetable stock, until slightly reduced, 1-2 minutes. Season to taste.

• Transfer filling to a baking dish and evenly spread mash potato over the top with a drizzle of olive oil. • Grill until lightly golden, 8-10 minutes. TIP: Drizzling with olive oil helps the topping to crisp and brown!

• Divide plant-based mince and veggie pie between plates. • Top with spring onion to serve. Enjoy!