Mushroom and Lentil Shepherd's Pie with Mashed Potato Topping

Rinse lentils and place in a saucepan with 3 cups of water. Bring to a boil, reduce heat, and simmer for 20 minutes until tender but not mushy. Drain any excess liquid.

Wipe mushrooms clean and chop into 1cm pieces. There's no need to wash them; a dry brush or cloth works best.

Heat olive oil in a large skillet over medium heat. Add finely diced onion, carrot, and celery, and cook for 8 minutes until softened. Add minced garlic and cook for 1 more minute.

Add chopped mushrooms to the skillet. Cook for 10 minutes, stirring occasionally, until they release their moisture and begin to brown.

Stir in soy sauce, tomato paste, and sesame oil. Add dried thyme and bay leaf. Pour in vegetable broth and add cooked lentils. Simmer for 15 minutes until the mixture thickens. Season with salt and pepper to taste.

Peel and roughly chop potatoes. Place in a saucepan of salted cold water. Bring to boil and cook until tender, about 15 minutes. Drain well and return to the pot over low heat briefly to remove excess moisture. Mash with high-quality olive oil and nutritional yeast if using. Season with salt and pepper.

Preheat oven to 200°C (400°F). Transfer the filling to a baking dish. Spoon the mashed potatoes over the top and spread evenly. Use a fork to create desired texture. Bake for 25 minutes until golden.

Let cool for at least 10 minutes before serving to allow layers to set.