Prepare the roasted leek. Preheat the oven to 180°C. Cut the reserved half leek lengthwise into long pieces. Heat a little olive oil in an ovenproof pan over high heat and cook the leek cut side down until well browned. Cover with aluminium foil and transfer to the oven for about 30 minutes, or until completely tender.
Prepare the stock. Keep the vegetable stock hot over low heat while you cook the risotto. I usually make a simple stock with vegetables such as carrot, celery, onion and dried mushrooms. Alternatively, use hot water with a little miso or a good quality vegetable stock cube.
Toast the hazelnuts. Toast the hazelnuts in a dry pan until fragrant and lightly golden. Set aside. Leave them whole or cut them in half for serving.
Make the leek cream. Heat a little olive oil in a pan and add the finely sliced leeks. Cook gently for about 12 to 15 minutes, until completely soft and sweet without browning too much.
Transfer the cooked leeks to a blender. Add the nutritional yeast, a little olive oil, salt and black pepper. Blend until smooth and creamy. Set aside.
Start the risotto. Add the rice to a wide pan and toast over medium heat for about 2 minutes, stirring frequently.
Pour in the white wine and allow it to evaporate almost completely.
Begin adding the hot vegetable stock, one ladle at a time. Stir regularly and allow most of the liquid to absorb before adding more.
Add the leek cream. About halfway through cooking, stir the leek cream into the risotto. Continue gradually adding stock as needed.
Cook the pear. While the risotto is cooking, cut the pear into small pieces. Heat the vegan butter and olive oil in a separate pan and sauté the pear over medium to high heat until lightly golden and just tender. Keep it slightly firm rather than cooking it until soft.
When the risotto is almost ready, add part of the cooked pear and gently fold it through the rice. Reserve the most attractive pieces for serving.
Mantecare the risotto. After approximately 14 to 16 minutes of cooking, taste the rice. It should be cooked but still slightly firm in the centre. Remove the pan from the heat.
Add the vegan butter and stir vigorously until completely melted and emulsified. The risotto should be glossy, creamy and still quite fluid. Taste and adjust the salt and black pepper.
Plate immediately. Spoon the risotto onto the plates and top each portion with a roasted leek piece. Add the remaining sautéed pear and the toasted whole or halved hazelnuts.
Finish with a few small lemon thyme leaves for freshness and subtle acidity. Serve immediately.