Vegan shepherd’s pie

1 In a large pan, add potatoes, sweet potato, squash and garlic, and just cover with water. Bring to the boil over high heat, then reduce heat and and simmer for 10-12 minutes until tender. Drain and return to the pan. Add dairy-free milk and spread. Mash until smooth.

2 Meanwhile, heat 2 teaspoons of the oil in a large non-stick frying pan over medium-high heat. Cook the mushrooms in two batches – add half the mushrooms and cook, stirring, for 5-7 minutes until golden and tender. Remove from the pan, then repeat with another 2 teaspoons oil and the remaining mushrooms. Remove from pan and set aside.

3 Heat remaining oil in the same frying pan over medium heat. Add onions and celery and cook, stirring occasionally, for 8 minutes until softened. Add flour, rosemary, half the thyme, a little nutmeg and the mustard, then stir to coat. Add stock, soy sauce and mushrooms. Bring to the boil, then reduce heat to medium-low. Simmer, uncovered, for 15 minutes until vegetables are tender. Stir in frozen peas and allow to heat through.

4 Heat the grill to high. Transfer the mushroom mixture to a 1.5-litre baking dish and top with the mash, spreading it roughly over the surface. Grill for 10 minutes until lightly browned. Serve sprinkled with the remaining thyme.