In a saucepan place the vinegar, sugar, ginger and water, bring to the boil, stirring until the sugar is dissolved. Remove from the heat and once cool, add the cucumber and allow to marinate overnight. In a small saucepan of boiling salted water, boil the quinoa for 10 minutes or until soft. Drain and set aside. In a medium saucepan bring the stock to a simmer, then keep warm. In a separate saucepan, heat the olive oil and 2 tablespoons of the butter, then add the onion and sauté very gently until the onion is translucent (5–6 minutes). Add the rice, increase the heat and stir constantly for a couple of minutes to toast and coat the rice with the oil and butter until glossy and slightly translucent. Add the wine, letting it bubble until it’s absorbed. Add ½ cup of hot stock and stir until it has been absorbed (ensure the heat is not too high; a medium simmer is best so the rice doesn’t cook too quickly). Continue adding the stock ½ cup at a time and stirring until absorbed. The process should take approximately 25 minutes and the rice should be al dente. When all the stock has been absorbed add the strained cucumber, cooked quinoa, wasabi tobiko, pickled ginger, the remaining butter and the Parmigiano, stir until thoroughly combined. Check seasoning, then cover and allow to sit for 5 minutes. Divide evenly among 8 plates and garnish with the extra tobiko and ginger, and serve.