Creamy Mushroom Cottage Pie (Vegetarian)

Preheat oven to 200°C (180°C Fan/Gas Mark 6).

Peel and chop the potatoes into evenly sized chunks. Place them in a large pot, cover with cold water, and add a pinch of salt. Bring to a boil and cook for 15-20 minutes, or until tender.

While the potatoes are cooking, heat the olive oil in a large skillet over medium heat. Add the onion, carrots, and celery and cook for 5-7 minutes, or until softened.

Add the mushrooms and garlic to the skillet and cook for another 5-7 minutes, or until the mushrooms are browned and have released their moisture.

Stir in the thyme and bay leaf. Pour in the vegetable broth and bring to a simmer. Cook for 5 minutes to allow the flavours to meld.

Mix the cornstarch with the cold water to form a slurry. Pour the slurry into the skillet and stir constantly until the sauce thickens. Remove from heat.

Stir in the double cream and season to taste with salt and pepper.

Drain the potatoes well and return them to the pot. Add the butter and milk, and mash until smooth and creamy. Season to taste with salt and pepper.

Pour the mushroom and vegetable filling into an oven-safe dish.

Spoon the mashed potatoes evenly over the filling, spreading them to the edges of the dish. Fluff the top with a fork for a rustic look.

If desired, sprinkle grated cheese over the mashed potatoes.

Bake in the preheated oven for 20-25 minutes, or until the mashed potato topping is golden brown and the filling is bubbling.

Remove from the oven and let it stand for 5-10 minutes before serving. Remove the bay leaf before serving.