Step 1: Put the Vegetable Stock on to heat.
Step 2: Separate the leaves of the radicchio and wash them well, then drain and pat dry. Bunch together and cut into 5 millimetre wide strips.
Step 3: In a deep frying pan or saucepan, sauté the onion in the Extra Virgin Olive Oil and butter until golden. Add the thyme and lemon zest and cook together with the onions.
Step 4: Add the chopped radicchio and toss to coat, letting it cool down. You may need to add the extra butter so that there is enough to coat the rice. Add the rice and toss to coat then turn up the heat and deglaze with the Verjuice. Allow it to evaporate for a moment on low. Season with sea salt.
Step 5: Add a ladleful of the hot Vegetable Stock to the rice and stir until incorporated before adding the next ladleful.
Step 6: Continue this process, stirring continuously, until all the stock has been absorbed and the rice is cooked but still a little firm (it should not have a chalky centre). This will take about 20 minutes. The last ladleful of stock might not be used; it’s a personal statement as to whether you like your risotto creamy or slightly runny. Remove the pan from the heat, then stir in the Parmigiano-Reggiano
Step 7: Add pepper and check the salt, then serve.
Step 8: Add Gorgonzola at the last moment. Garnish with chopped flat leaf parsley, and serve with a squeeze of lemon and freshly ground black pepper. Add extra Extra Virgin Olive Oil if desired.