Preheat your oven to 180°C (160°C fan)/350°F/gas mark 4. Line a loaf tin with baking paper.
Roughly chop the nuts or pulse them in a food processor until they are coarsely ground. Set aside.
Heat the olive oil in a frying pan over medium heat. Add the onion and garlic, and sauté until softened. Add the mushrooms, carrot, and celery. Cook until the vegetables are soft and any liquid from the mushrooms has evaporated
In a large bowl, combine the cooked vegetables, ground nuts, lentils, breadcrumbs, and cranberries. Add the soy sauce, tomato purée, mixed herbs, and season with salt and pepper. Mix everything thoroughly until well combined
Spoon the mixture into the prepared loaf tin, pressing down to ensure it's tightly packed.
Place the loaf tin in the preheated oven and bake for 40-45 minutes, or until the nut roast is firm and golden on top.
Allow the nut roast to cool in the tin for a few minutes before carefully turning it out onto a serving plate. Slice and serve warm, perhaps with your favourite vegetables or a gravy.